just for reference, people talk about CDs (cycle days) and DPOs (days post ovulation). So you'll have 28ish CDs and 14ish DPOs per cycle (if that makes sense!).
So... here's how you count it/refer to it:
-CD1 (cycle day 1) is the first day of your period.
-usually you ovulate around CD14 (cycle day 14).
-from then on, people usually talk about "DPO". usually, you'll start doing pregnancy tests from around 11DPO (11 days after ovulation), and a positive usually shows up no later than 15DPOish.
-when you period reappears (usually around 14DPO), a new cycle has started and you begin counting from CD1 again.
(i'm just including all this so you'll know what people are nattering on about on conception threads)
to work out your cycle...
i used temperature charting and OPKs (ovulation predictor kits -- like a pg test, except it tells you when you're about to ov). the combination was perfect... i was pregnant on my first month trying, after almost 15 yrs on the Pill.
check out fertilityfriend.com if you want to give charting a go. All it is, is you buy a fertility thermometer (you can get them in Boots... they give your temp accurate to 2 decimal places), and then every morning before you get out of bed, take your temperature and record it.
when your morning temp dips suddenly and then shoots back up a day later, that confirms you've ovulated. i used OPKs at the same time because the OPK gives you a 24-hour warning that ov is imminent. the temperature pattern will then confirm it. (knowing you're going to ov means you have time to get shagging during your most fertile period). fertilityfriend is useful to track and interpret your temperature pattern, you can also add OPK data and that helps get a more accurate picture of your cycle.
you can also use the cervical mucus method, but some women don't get the "egg-white mucus" that every talks about so it's not as useful to some. but i think many women have found that method really effective.
btw, your body will also give you little cues. i found that ovulation = ladybits noticeably engorged for a day or two, especially inner bits around vagina. that never happened while i was on the Pill, got quite a shock!
hth!