Please help if you can!!?

I am ttc but I have PCOS and my periods are very irregular! Some months I don't even have a period and the no of days between each period changes each cycle. I have some ovulation sticks but don't know when best to use them as don't have a clue when I'm ovulating!! Also I heard that lubricants and even saliva can harm sperm is this true? Your help is much appreciated.