I need help ! Please ??

Bare with me.

I've never kept track of temp

Been TTC 6 months .another Fail (Cd1)

I use opk and its pin pointed perfectly did get pregnant once miscarried in july

My dr recommended bbt

so here's the run down

Specific thermometer?? Can I use any kind ??

Says to take before getting up . What if I pee at 3 am?? I'm up at 6. Do I temp at 3 or 6 then?

I'm just looking for some insight seeming this is my first month . I missed today but heading to walmart and want to make sure I have everything I need to start tomorrow correctly! Thank you!