I start seed year round. I generally just keep my seed very humid, warm, and in partial shade to full sunlight for the first few weeks and then move them to full sunlight if I can. For Lophophora, you will see they are just right when they are nice and round from the moment they sprout. If they elongate, you have not given them enough light, but no worries as this can be rectified simply by giving them more light slowly. I frequently have my seedlings turn red or purple from too much light, but this is again okay as they will outgrow it and grow perfectly fine so long as they are slowly introduced to the amount of sunlight in question. I basically treat my Lophophora and Trichocereus identical to each other for germination, grafting, and growing purposes for the first several months.
Hope that helps.
When I graft you graft we graft