I don't know if anyone is going to agree with my methods but here's what I do: because my chicks are in the house, I keep the heat lamp on them for a couple weeks or so. The regulated temp is needed, and I know they'll be warm enough with it on all the time. However, I honestly feel that every living thing needs night time... everybody needs a regulated schedule of light and dark... so, after a couple weeks, I bring in a small space heater. I set it on a low setting ( if I can stand to stay in front of it for a looooong period of time without feeling too hot, it's probably ok for the chicks) It freaks them out to have sudden darkness, so I begin turning lights of gradually - heater on, heat lamp off, then house lights gradually - I know, I baby them, but I don't want to cause too much stress... they freak out for a while until they get used to dark-time. Getting a good nights rest seems to be good for them, they wake calmer and they're easier to handle. I GET SLEEP THIS WAY TOO!
PS... in about 6 weeks (once its warmed up at night) they'll go outside full time. I start introducing them to dirt and grass and good ole Sunshine right away though...