day 1 of ivf cycle

Hello everyone... can someone help please!!

Am about to start my 2nd round of ivf/icsi soon and must have day one of my period early july... how can i manipulate that this comes then? i am still waiting for my period for last month!! (no not preggers and i was going to go on pill before my july day 1 to make sure i can have a period again early july as possible... i think i may be at the big O right now (now use to me cause cant get preggers without ivf) so prob 12 days time should get my AF (approx 22 june) .. that means can i have an extra SHORT cycle after that if i stop the pill just on first week of july? and should i get my period again then? then i can make THAT DAY my day 1 for this cycle... i dont want to mess anything up.. just a real pain that my cycles are all over the show!!!
Any good advice much appreciated... Bye the way i need to have this cycle start early as possible in july and have the ivf cycle all done and dusted before end of aug (may have work commitments early sept) so hoping for good timin here!!