tips for fertility awareness method of birth control?

K
I decided to stop birth control for a while because it was making my depression and anxiety unbearable. I've been looking into fertility awareness methods..does anyone have any tips for making this method the most effective as possible? How effective is it really? I use glow to track (but going to track outside of the app too) and am researching stuff but I'd like to hear any personal tips or experiences you guys have had with this. 
I really really miss my partner finishing inside me but I'm also very paranoid lol. Any help is greatly appreciated!!