Fill out the brief Membership form, then follow instructions. You can also build a free page on AOL, Geocities, Tripod, Angelfire, and many others. But assuming you don't have AOL, or don't want to get it, your best bet is one of the others. All you'll need is Web access and an email address. Geocities has an amazing number of personal pages on its site, and offers both basic and advanced site creation.
Tripod is similar, though with a smaller number of sites.
Both offer up to ten megs of space, however, as well as lots of other goodies. Angelfire offers less space, but is probably the easiest of the three to use. There are others, but I can't personally recommend them. Finally, you could try A Beginner's Guide to HTML . You're going to want some graphics for your site, and there are a lot of great places to get free Web clip art.