Welcome to charting! Which charting program are you using? I can tell you how to link a Fertility Friend chart if that's what you are using.
You are right that you need a bbt thermometer and you do want to record that temperature. Also, you may find it helpful to record your CM and any symptoms you are having. I keep track of when I've taken vitamins or any other meds too so I don't forget if I've taken them.
I use OPKs most months b/c it helps me to ensure that I have O'd. I've gotten them from a variety of stores (including internet cheapies) and they seem to work pretty well.
Best of luck!!