Designing an online form may not be as glamorous as creating an animated Flash movie or dreaming up cool ad copy. But for many Web sites, online forms are an important marketing tool—and often the place where actual revenue is generated.

Whether you're a community site trying to gain new members, a news site aiming for more newsletter subscribers or a financial site processing loan applications, your online forms can be indispensable to your business.

Here are eight tips for creating forms that succeed.

1. Shorter Is Not Necessarily Better

A mantra of online form design is “shorter is better.” Of course, this is common sense. Ceteris paribus (“all other things being equal”), who wouldn't prefer a shorter form to a longer one? But, as the Latin phrase hints, consumer preference depends on the context.

For example, if you're promoting an e-newsletter subscription, you probably need only two pieces of info: email address and permission to subscribe. However, if your form asks only these two questions, some users may be turned off. Asking relevant questions—contextualizing the offer—can lend credibility. For instance, if the newsletter is aimed at graphic designers, you could also ask what platform they're on and what programs they prefer. Adding minimal contextual questions won't discourage many users from completing the form; in fact, it will probably reassure them.

2. Design Multiple Pages—or Not

Besides deciding on the number of questions, you also need to decide on the number of pages. If your form consists of 20 questions, should you build one page with all 20 questions, or do you create two pages with 10 questions each? Of course, the correct answer is to try both—and compare completion rates.

However, there is a key advantage to splitting your form into multiple pages. If you ask essential questions on page one, and the user abandons later in the form, you will have at least acquired your essential data. For instance, if you ask for email address and permission to market on the first page, you can communicate again with users who didn't fully complete the form.

3. Minimize Outside Distractions

The golden rule is, don't distract users while they are completing your form. You must minimize any components that can drive users off the form. Resist the temptation to place banner ads and other promotions on transaction pages. You don't want to give a motivated form completer an opportunity to opt out right when they are completing the form.

4. Don't Over-Design

It's tempting to incorporate extra visual elements in your form, especially if they've worked well elsewhere on your site. However, you should consider building a more understated form. Clean, minimalist forms not only avoid visual distractions but also project an aura of trust. A perusal of major Web sites will show that streamlined forms are the norm—even on flashy sites. Giving personal data is an exercise in trust; you can reinforce this by creating a clean and trustworthy page.

5. The Word About Copy

As with design, follow the minimalist approach in writing copy. Users often scan instructions quickly. After all, they've been completing forms—online and off—for most of their adult lives. If you do need explanatory text, hyperlink specific questions to small pop-ups. Users can get the answers they need, and move on.

6. Be Aware of Browser Compatibility

A recent study by OneStat.com indicates that more than 95% of Internet users worldwide use Internet Explorer as their Web browser. This materially simplifies the process of developing online forms. Unless you're a specialty site, you'll reach the greatest share of users if you build the page to be optimized for Explorer.

However, there is still variability across platforms (Mac, PC, WebTV), and it is also inevitable that some users will not be able to use your form for other reasons (e.g., JavaScript is disabled). So, it's worth considering having a backup plan for these users. Their numbers will be small, but some will complain. An email option is an easy solution.

7. Ensure Security

As mentioned above, providing personal data is an exercise in trust. This is especially true if you collect sensitive data. To encourage users, you should show tangible signs that your form pages are secured. You can do so in a low-key fashion so as not to distract all users. The ubiquitous yellow lock icon at the bottom of the browser window is one example.

8. Don't Reinvent the Wheel

Completing forms is a common experience for Internet users. In designing your forms, you should use the standard UI elements that other sites use. For instance, asterisks are the standard symbol denoting required fields. There is no need to confuse users with different ones.

More generally, all kinds of forms—registration, subscription, financial—have been built, used, tested and optimized by the most successful Web businesses over the last several years. You should leverage their learnings. Building upon existing Internet wisdom will help your forms serve your audience, and convert for your business.