If there is a single secret to selling online, it is to work hard. Hard work is the secret to succeeding in almost anything, but it is especially important on the Web.

It's true what they say: the Web levels the playing field. A high school can make a better Web site than a large industrial company. On a level playing field, how big you are matters less than how hard you work.

There are millions of consumers out there, but lots of other Web sites are competing for their attention. So you can't just build an online store and walk away from it. You have to work hard to draw visitors to your site, work hard to create a site that those visitors want to buy from, and work hard to give those buyers such good service that they and their friends will buy again in the future.

So the bad news is that starting a business on the Internet is just like starting any other business: work, work, work. The good news is that it is a lot cheaper.

The Web gives you something that has never existed before in history: an inexpensive sales channel direct to consumers. Before the Web, if you wanted to sell direct to consumers, you either had to build retail stores or do catalog mailings. In either case the entry fee is hundreds of thousands, if not millions, of dollars.

On the Web, you can sell direct to consumers worldwide for a hundred dollars a month. You have to work hard to exploit this opportunity. But if you are willing to work hard, you don't need a lot of money to get started.

What sells online? That is probably the question we get asked most. At the risk of being repetitive, what sells online is work. In our experience, the difference in success between one store and another depends a lot more on how hard they work than on what they are selling.

I know of two stores, Store A and Store B, that are selling exactly the same products. Store A sells five times as much as Store B. The reason is, Store A works a lot harder. They work on their site almost every day, and they also do more to promote it.

But although work is the decisive factor, what you sell matters too. As a general rule, whatever sells in print catalogs will also sell on the Internet. If the customer has to see something before buying it, then you probably can't sell it in a print catalog, or online. Otherwise, you should be able to sell almost anything.

It's true that more men use the Internet now than women, so if you sell something that men buy, you are likely to have a slight edge. Someone who works with computers is almost certain to have Web access, so anything computer-related is likely to do comparatively well. And Internet users are richer and better educated than the population as a whole, so luxury items may do well.

But these trends are not set in stone. When televisions first became available, the first buyers were probably richer and more technologically inclined than the population as a whole. But TV rapidly became mainstream, and the same thing is happening to the Web.

More important than the type of products you sell is the size of the niche you choose.

In the physical world, niches are based on geography. I often buy food at the corner store near my house, despite the small selection and high prices. If this store were more than 100 yards away, I would never buy anything there. But in the physical world, proximity is king.

Not on the Internet. Geography is almost irrelevant on the Internet. Niches on the Internet are based on what you sell, not where you are. And whatever you sell, you have to be the place to buy it, because your customers can just as easily visit any other online store.

So you have to choose a niche small enough that you can dominate it. For example, if you are a tiny company, it would probably be a mistake to try selling top-40 CDs online. You would have a hard time competing with CDNOW. But you would probably have a chance at becoming the site for European folk music.

One certain way to dominate a niche is to be the manufacturer. For example, Harbor Sweets is going to be the site for buying Harbor Sweets, because they make them. Manufacturers may be the biggest winners on the Internet, especially small manufacturers who have till now been at the mercy of the channel.

In a print catalog, "production values" refers to the quality of the paper and printing processes used, the number and quality of images, and the care taken with graphic design. High production values are critically important in catalogs, which have to convince consumers to buy based on a few sheets of paper.

Production values are even more important on the Web. Consumers will not buy from an amateurish Web site.

Most of the people who visit your site will still find the idea of ordering online unusual. I have been buying online for two years, and I still find it a little unusual. So your site needs to inspire visitors with confidence. It should say that yours is the kind of company that does things right, and that if I order something from you, it will be a good experience.

Of course there is no direct connection between the quality of your site and the quality of your company. A company could have a brilliant graphic designer and lousy products. But usually there is a connection, and that is what visitors to your site will assume. If your company is unable to put up a good Web site, then it seems natural to assume that your company cannot deliver good products or services.

The most extreme case, of course, is when your company does not have a Web site at all. Occasionally I go to look for information about some product, but find that the company either doesn't have a Web site, or has a site with nothing in it. Not impressive.

Almost as bad as the empty site is the site that looks amateurish: for example Dot Pets or ayurvedic resorts.

Overall the most important feature of a Web page is the organization. That is what visitors will notice first. It should be possible to "read" the structure of a page at a glance. A high quality Web site looks clear. A badly designed site looks haphazard.

Of the elements on the page, the most important are the images. A Web page consists of text and images, and everyone's text looks the same, so the difference in production values between good sites and mediocre ones depends almost entirely on images.

By images I do not necessarily mean product images. I mean gifs and jpegs, whether they are product images, display text, logos, button bars, bullets, or what have you.

To start with, better Web sites usually have more images. For example, they tend to have button bars at the top of each page, to brand the site and to aid in navigation.

In particular, avoid the common mistake of putting a huge image on your front page. By all means put your logo on the front page, and in fact on every page, but make it download fast. Your logo is not what your customers came to see.

They came to see your products. But don't throw full-size product images at your visitors until they ask for them. Sophisticated sites begin with a page of smaller thumbnail images, which visitors can click on when they want to see more.

Make your product images as high quality as possible. Consumers won't buy from an image that looks like a badly lit polaroid. So have a professional photographer take your photos. Images shot with a top-quality digital camera look brightest, but you can also scan transparencies or even scan images right out of your print catalog.

If possible, try to make the background color for the product images either the same color as your pages, or transparent. Product shots look better when the object seems to sit right on the page.

Finally, don't make spelling mistakes in your site. A few of those will undo all the other work you've done to make your site look professional.

It is no accident that the people who visit your site are called "Web surfers". They have the same short attention span as TV "channel surfers". The average visitor to a Web site looks at only three or four pages before going somewhere else. Visitors will leave at the slightest obstacle.

So if you want people to visit and order from your site, don't put any obstacles in their way. Whatever you do, don't force visitors to register. You have to create yourself an account, with a user id and password, before you can even order from Wal-Mart. Do they expect online shoppers to remember a userid and password for every online store they visit?

Most major sites have learned not to require registration. They have also learned not to use frames. Frames are a lot more gratifying to the site designer than the visitor. To visitors, frames are merely confusing.

For example, frames make the Coach site so hard to understand that nearly all the text on the first page is navigation instructions. If the site were easy to navigate, Coach could use that space to present their products instead.

Another big disadvantage of frames: most search engines don't index sites that use frames. Most sites get most of their hits from search engines, so not being included would put you at a crushing disadvantage.

None of the most heavily visited sites use frames. In fact, the more important the site, the simpler the design. Look at Yahoo! There are no bells and whistles to distract you. The design of the site is so simple that you get it at a glance.

Most of your visitors will not start at your front page. Most of your hits will come from search engines, and when someone searches for a phrase in a search engine, they are sent directly to the page in your site that contains that phrase. So most of your visitors will drop right into the middle of your site, like paratroopers. The design of your site has to tell them immediately where they are, and what their choices are.

Most major sites solve this problem by putting a row of buttons at the top of each page. Within the buttons they include a small version of their logo. The logo serves two purposes: it brands the site, and it serves as a link back to the homepage. For example, look at these interior pages from CDNOW, ISN, and the NASA store. They all use this approach. So does Yahoo. It has become the accepted convention for the way a site should be organized.

Make sure you put these links at the top of the page. You don't want new arrivals to have to scroll down to the bottom of the page just to find out where they've landed.