that you, literally, push or project yourself "outward"
but that won't work
what you do is make yourself "compatible" with astral projection . . . so you don't strain and push but, rather, find the space within yourself which is "aligned" with astral projection
in English, you work on yourself . . . keep working on yourself
and wait
good things come, at least spiritually, to those who both (a) do "the work" and (b) are patient