How long should a girl wait ?

how many days should a girl wait before having sex after her periods?

Well, to be on the safe side, I heard that a woman becomes more fertile when she finishes her period so in estimation at least like a week after or so. Its up to you really, but just wear a condom when you do.

You can have sex anytime you want: before, during or after! If you want to avoid getting blood on your partner then I'd say the last days of a period or when you see you aren't bleeding anymore should be fine.