The best one I ever came across is qi cultivation from the cosmos plus running the microcosmic orbit. There’s a quick summary here, and books are in the Rook Recommendations Collection.
The second best was the energy work in the Monroe Institute gateway meditation tapes.
In both you basically put your mind to feeling as far out in the universe as you can imagine, and breathe in the energy. You use your breath to control it.
Also look up “pore breathing” for a modern occultist’s approach to the same idea. .