We use NFP, right now to postpone pregnancy. We have even used it successfully for about 3 years, even during the last year when my job required me to travel 5 days a week. It is not always easy, but I wouldn't trade the freedom from condoms and the diaphram for anything. Both families tease us incessantly about going crunchy with "that family stuff" and my girl friends think we are crazy "how can you control yourselves...", but it works for us. No surpise pregnancies. In fact, we like it so much that we now teach other couples how to use NFP! If anyone is interested in knowing where the < 2% divorce rate for NFP couples or 99.8% effectiveness stats come from, let me know. Call me OCD, but I HAD to know where the numbers came from.
When we were engaged, I wanted to go the Pill. Why? because everyone I knew I was on the Pill and it was going to make my skin beautiful.
Ironically, my husband was the one who first brought up the idea of NFP. He had read some medical articles about long term hormonal use and didn't want me on them. We later learned the "mini pill" (progesterone only) are abortifacients. I hope I don't sound preachy; I only want to pass along what I have learned. These "miscellaneous details" were not easily available to use when we were trying to decide on BC.
Now, for the practical details: I take my temp in the am with a digital therm, for about 15 seconds. We've used the mercury therm, (takes about 3 minutes). That was so fun when my DH would "shake it down" at night. This humored us to no end. The charting quickly became part of our daily routine. I used to chart on paper, but now I use a software program. Another bonus, the abstinence period creates a monthly honeymoon. We cherish that time together---not that you can't without NFP--- but it does add a celebration mood to the whole thing.
For anyone intersted in learning more, I agree, TCOYF is a great resource. The Art of NFP provides some additional resources for interpretting charts when you have irregular cycles, are breastfeeding, or are premenopausal. The Families of the Americas is another excellent resource. All of these are accessbile online.