I charted temperatures when ttc Charlie, we were trying for about 6 months then I started charting and fell pg on my second month taking temps!
You are suppose to take your resting temp at the same time after atleast 3hours consecutive sleep and before you move etc.
I use to set my alarm at 5:30 every morning, take my temp then go back to sleep.
You can either take it externally or internally, so long as you stick to the same method you'll be fine! I use to take it vaginally as there was nothing that could effect the temp there lol so the reading would always be true!
I found it really beneficial to me because you can confirm ovulation definatly happened, and you know af is going to arrive if your temp drops, it took the anxiety out of ttc for me.
I knew I was pregnant before doing a test as well because my temp remained high!
What info were you after?
I used fertility friend to keep track, I also use to take note of cervical mucus and cervix position!