Need guidance

Hi ladies! I am ttc for 6 months..and in this whole duration we baby danced almost everynight right after periods until AF arrived (we thought this would increase our chances). But still no positive result.My periods were very regular but in last 3 months they always come 8 to 10 days late..and those days are like hell.waiting for a bfp but instead you get bfn. I don't what we are doing wrong. This month i am going to track my ovulation (but i don't know which day i should start testing because of my last irregular periods). and gonna use preseed aswell (i read so many mixed reviews about it so thought to give it a shot. if someone got a bfp through it plz tell). just need some guidance and answers to my question. Baby dust to all. ☺