The more you test the better in my book. However before my CGM, how much testing I did depended on how I seemed to be doing for the day. I would test anywhere from 3-8 times a day, but I was on insulin and so it really mattered.
I am going to assume you are not on insulin as a type 2? So testing is more so you know which/what foods how you are reacting and how they are changing your BG level. Maybe also so you know how careful you have to eat the next snack/meal? Or exercise etc. And mostly to make sure you are getting control of your Bg levels.
So I believe how many times a day would be up to you. However if you ever don't feel "right" always test!