You have to inspect yourself twice a day, once in the morning when you wake up, and once before the shkiyah, the sunset. If you miss one, you have to call a rabbi and ask if it’s okay or if you have to start over from the beginning. If you inspect yourself one day and there’s no blood but there’s a stain, you have to take it to the rabbi so he can say whether it’s kosher or not. If your underwear is dirty, you have to take that to him too. Or you can send your husband.
