Ay sis, honestly ang best time talaga is first day ng period mo para walang doubt, pero pwede mo rin seryoso anytime basta sure ka na hindi ka buntis, a few of us actually started mid-cycle and it was fine! The important thing is talk to your OB muna about which method works best for you (pills, IUD, implant, whatever), kasi iba-iba ang timeline depende sa type, and if you just gave birth, may special rules din based on breastfeeding situation kaya definitely consult your doctor para safe and effective talaga.