OK, I use PHP form in some of my pages to gather information for telemarketing like a home made CRM system. I would like to use the write form data to .csv file option in the form properties in each page. How do I set up the excel in the program and how do I get the form to point to the file?

I am not new to excel but I am when it comes to this function, this would really make my business move much faster, as a client adds their information it should add to the .csv file?