To add a hit counter to your page, just follow these steps:
<!--#exec cgi="/cgi-bin/counter"-->
Every time someone loads your document, the counter is called. The counter starts at 1 the first time it is called from a page, and goes up by one each additional time it's called. If you rename your file, the counter will start over again at 1. Be careful not to use the counter more than once in the same document, or else it will add one more hit for each extra time you use it!
That's all there is to it! Here's what the counter will look like when you're done: