That is very hard, since you are irregular. For normal fertility a woman will ovulate about once a month( some more than once). This normally happens about 14 days before your next period. For example if your period is 28 days long you will probably ovulate on day 14. 28 minus 14! To make sure there are sperm present you should have sex on day 10- 16 after the first day of your period. This will help to increase your chances. I went with this method and have been pregnant twice this year. Unfortunately lost my first baby!

i understand but, what about for irregulars?

My advice would be to have sex every day, or at least every other day, and it's bound to fall on your fertile days. Not a guarantee you will fall pregnant of course but it'll increase your odds!

Every other day - it increases your chances, every other day can lower the sperm count due to how sperm is produced.

It is very hard to track the cycle if you are irregular, but if your cycle is normally about 45 days then you could expect ovulation to be about day 31 (ish) so sex every other day from day 26 to day 33.

Charting your cervical mucus and your basal body temperature can help you learn when you ovulate.
Google "fertility friend" and they have some fantastic tutorials on how to do this and they also enable you to chart online. If you chart your temp the site will estimate when ovulation is for you too.

ah good point! Yes, evry other day then - don't wanna wear those bad boys out!

why dose every other day lower sperm count? I thought it raises sperm count. How do you prevent it from lowering sperm count?

Sorry I mistyped.
Every day lowers the number and quality of sperm.
Every other day increases the number and quality of sperm.

Aw?---kai ...Thanks alot that really helps! I can stress about the littlest things which delays everything.