I wait till at least day 14, that way you're stripping babies and not eggs.
I drain some tank water into a bucket and put the fish in it. With my right hand I hold her. I use my left fingernail to gently open her mouth. Some babies will come right out. For the ones that don't, I VERY GENTLY tap her throat pouch. For the last stubborn few ill turn her face down in the water and kinda dunk her.
Now she's got air trapped in her little body, so turn her face up and lower her into the water. The air will escape.
Put her back into the tank, and you're done!