I wait till my silkie has been broody for at least a week and then I sneak the chicks in under her. I let her sit on plastic easter eggs and then when the chicks "hatch" I break open the plastic eggs as I put the chicks in. I doubt I really even have to to do that, they are such insistend mothers. With some of my other breeds, it seems more succesfull to put the chicks in in the evening after sunset. Most of the time I can't wait though. I've had only one chick rejected by the hens so far and that one ended up with a severely crossed beak, so maybe the hen knew something was wrong with her.