If you've got a website with content that you want to sell or protect from consumption by the general public, you have to password protect it with a log-in form. When your web visitor arrives at your protected web page, he will be greeted with a welcome message and a form that requests his user name and password. With a log-in form you can also manage and track the usage of your website visitors.

Find a Site Membership Service

There are a number of online services, like CoffeeCup.com and Authpro.com, that do the hard work for you when it comes to creating log-in forms for your website. You can establish an account and manage your membership data (such as user names, passwords and customer email addresses) directly from the service's online or offline software. This is more professional and efficient than attempting to create a standard form from scratch on your own web server.

Establish Settings

After you have established your membership services account, you must add a few pertinent settings to your account in order to accept and route members properly. Enter the address of the web page where you want users to login as well as the destination page. If you plan to require a subscription payment from the customer, you have to provide information about your merchant account or payment services provider (such as PayPal). Set the colors and general design of both your login and registration pages as well.

Install Code on Web Pages

The membership website service will provide you with a line of page protection code after you finish establishing your settings. You must add the code to the header tags of all of the HTML pages on your website that you want to protect. Thereafter, whenever a customer types in the web address, he will see the log-in form. He will not be able to access your content without a valid user name and password. You can delete and add members from your list of users manually using the membership services provider's software.

Source:

ElitebyDesign.com: Examples of Login Forms on Websites

Authpro.com: Example of Membership Services Provider Settings