go to sleep like usual, and if you have a time in the night where you wake up and then go back to sleep try to concentrate on just relaxing but staying awake, for most people this is how they accidently OBE for the first time. so just sleep for about 4-5 hours and then wake up, walk around for about 3-5 minutes and go back to bed. thats really my only sure fire technique thats worked for myself.