If you're interested there are articles about people who tried themselves or with the help of friends at home, in the 70's or so. I read about it a while ago, b

If you're interested there are articles about people who tried themselves or with the help of friends at home, in the 70's or so. I read about it a while ago, but although it's an interesting read there's no clear answer (people were already into it enough to perforate their own skulls, so their account isnt very subjective, and they were usually into the paranormal, "energies" and similar pseudoscientific ideas).