Long Down Reg - Got AF - when to take the pill?

Hello everyone - need some help!!!

Had an appt with a new FS and just had my lap done - no endo just a stuck ovary BUT he said make an appt to see him in 3 weeks. I remember he said on initial appt that am going to be doing a long down reg on the pill when AF arrived - which is today!!!!..so I had rung the receptionist who sent me out the script for the pill. (i'm guessing take the pill for 3weeks)

Problem is how do I take it?..today is AF so do I start on the sugar pills or is it totally different with ivf - do I start on the 'other' pills'. I've googled and some say take it on day 3 of AF???

I haven't got my plan yet as waiting for NK cell levels test results.

Anyone done this type of cycle with good results?..so not use to this long time

Thanks again - Hope everyone's going along good with babydust to all. xox