a relatively standard way of managing it is to set up an application variable to record the number of hits.
Each time the page is rendered you increment the counter with a function.
Then you need to decide when and how you want to capture the count.
You could use the application onend event to write it out to file (and the application onstart to prime it) or you could use some other method. Generally I will record the count every 10 minutes or 30 minutes or similar so that if the application does not end correctly you don't loose all your counts.
Perment storage of the data could be to the file system as a basic text file or a db or something similar, but it would depend on what you have access to.