Best way to conceive! Help I'm new!

I was surprised to be pregnant with my daughter 3 years ago, so needless to say I didn't need to TRY to conceive. Now we are trying for our 2nd and it's been 3 months and I feel like maybe I don't know the basics. This app has helped (used it for 1.5 months now) but I just feel like I'm getting so much info! So do I have sex everyday of my fertile days? Every other day all month? When and why would I take an ovulation test? What kind of cm says you're ovulating? Any help is so appreciated!!