You can start temping whenever you want! It's best to start during AF or right after though, so you have a full month of temps.
If you go to FertilityFriend.com, they have free charting software as well as a tutorial program to walk you through everything--it's great! That's how I learned to chart.
Also, the book Taking Charge of Your Fertility is GREAT for learning about your body. Every woman who TTC should read it!
Anywho, your girls are adorable!

and I hope you stick around here and post some more!