Opk help

My partner and I are looking at trying to do our first IUI in november, I have an appointment with my OBGYN on the 28th of October and I have been trying to be proactive and have been gathering my bbt and when I can my CM since July for this appointment, but my question is if and when should I start using OPKs, should I start now even though my period is not regular or should I save my money and just wait till my appointment? With my PCOS I have a period about 4 times a year because of medicine, normally it would be once or less a year. I am not sure with only having a period 4 times a year when I ovulate... Anyone with the same issue and has some advice?