The level you can project on depends greatly on how your chakras are wired, and on how active they are at the time. Energy work can change how your chakras respond during OBE exit, and can thus produce higher level experiences.

Apart from setting your intentions and doing affirmations 'I project out of my crown chakra' before and during the OBE session (not during the actual exit as you need to keep your mind clear for this) there is no special technique involved.

robert