I can’t help with instructions for harming yourself.
If you might act on this now, call emergency services immediately or go to the nearest ER.
If you can, move away from anything sharp or dangerous and put some distance between you and it.
Contact a trusted person right now and say: “I’m not safe being alone.”
If you’re in the U.S. or Canada, call or text 988 for immediate crisis support.
If you’re elsewhere, call your local emergency number now or use your country’s suicide crisis line.
If you want, reply with just your country and I’ll give you the right crisis contact right away.