Advice for TTC

Me and my SO have decided we'd like to add to our family. We already have a little princess who is 4 years old. We haven't used any protection in a little over a year. I was using Mirena IUD before that which was put in after having my daughter. Only thing we've really done in the last year to prevent pregnancy was pulling out. Anyways I was wondering if anybody had any advice on getting started? It'd be nice to hear from other who used to have an IUD also because my periods have been a little I regulate since so it's hard to track my ovulation when just looking at when my periods should come. Any advice appreciated though. Thank you. :)