I'm charting my cervical mucous per Katie Singer's 'Honoring Our Cycles' book (which is nice and simple but damn! so conservative with the constant references to husbands and being married!).
For the first three months I'm going to test my LH levels with a Clearblue kit from day 11 onward, to see how well this lines up with my own observations.
I will use Lea's Shield (no spermicide, until I can get some of the non-Nonoxynol 9 stuff delivered), and withdrawal, from whichever comes first, wet vaginal sensation/sticky mucous or LH level spike, until whichever comes last, three days post-LH spike or a 24 hour period has passed without wet sensation/sticky or egg white mucous.
For background: I have a very regular 30 day cycle and am in a committed, monogamous relationship with someone I'd prefer not to get pregnant to just now, but suspect would like to parent with in the next couple of years. Both of us have been tested for the usual STIs. I don't want to use hormonal contraceptives and neither of us like condoms.