i start spraying 1 to 2 weeks b4 flip..then another week er 10 days after flip...usually i try to spray em 2x a day but then sometimes i only doit 1x a day..kinda depends on how lazy i am that day...i keep watch on the pods to see when they ready to drop pollen and then i take pollen and dust the buds i want seeds on..i use some tweezers to pull pods off if they only opening one here an there...can use a pc of glass or mirror ect to put pollen on too an use a Q tip ot lil artist brush to move the pollen,,if the plants are small enuff u can just shake the limbs with pollen on over other plants limbs ect to dust pollen...lotta diff ways..i have several of those dark green/black welders glass lens to put pollen on....GL