Welcome! I would start once a day in the morning before you brush your teeth or eat or drink anything. Coconut oil is very powerful, so if you are just starting this, then definitely only once a day.
Regarding seeing benefits, all I can say is your mileage may vary. For some its within a couple days, others months. I have no idea how long it took my husband's bumps to go away because we were not focused on them. He had been OPing for about 6 months when I just happened to notice. We were both surprised.
So I'm afraid I can't give you a specific answer on that. The first thing you may notice is how white your teeth are getting. That seems to be the very first thing that happens.