typically i start off with 2weeks of 24 hours of constant light, from germination on. personally i think this keeps the soil warm and keeps moisture buildup from happenening and mold setting in early when the seedling is most vulnerable
after that its 18/6 untill im done vegging. you can veg a plant on this cycle for 12months if you want, as long as its not an auto-flowering strain
once ive vegged it out i switch to 12/12 untill trichromes turn milky
once ive scoped the trichromes i kick it back to 8/16
and when 80% of the trichromes have turned amber i give it 48 hours of uninterrupted darkness and then kill the bitch.
ive gotten some killer beer can sized buds from bagseed using this lighting schedule