Hello, I had a miscarriage in April 2012. I am having trouble becoming pregnant. My last four cycles have been irregular and having trouble trying to figure out when im ovulating. I also wonder what would the method be since my partner works out of state and we only have sex approximately every 4-6 weks.
You are in a difficult position, because with irregular periods it is difficult to predict the day of ovulation, and you don't have sex often.  You can use an ovulation predictor kit to help you, but I would suggest that you speak with your doctor.  Your actor will be able to prescribe you medications that will make your ovulation more regular and predictable so that you can time our sex better and make it easier to get pregnant.  I wish you the best of luck!