question! please answer

Hi! So we have been trying, but kind of just going off of my body and when it says I'm ovulating as well as my two apps (glow and ovia). So my question is if I were to start taking my temp and tracking that, what am I looking for? A spike up or down? What time of the day is best to take my temp? I probably sound like an idiot but I'm sick of getting bfn so if I can try a new way of tracking I'm all in, just need help from you ladies!