Hello. Help!!! Ovulation planning kits

Hello. I am on day four of my period and my husband has finally after three years said yes to another baby. We already have two. Our first daughter was conceived on day 9 and our little boy 3 months after conceived on day 23. I am very thankful and appreciate how lucky I am to have my two beautiful children (who were both unplanned) but really have no idea how I fell pregnant with them and now I am trying to have another I have no idea how to time it!!!. My husband and myself have been have not been using contraception for over six months now and it seems that all the mucous method etc is not happening for us. I purchased the Confirm planning kit yesterday. Has anyone had any experience with these? Any hints would be appreciated as I really would like to complete our family. Thanks heaps.