Without intending to be funny,
if you have to ask, you shouldn't do it.
Particularly since the first aid for HF, calcium gluconate gel,
is not longer available (the company making it, I guess, got tired
of getting sued by idiots who could not be bothered to read
the FINE directions).
Start with Smithell's reference and follow references as necessary.
Read all safety instructions thrice (not twice, thrice).
Then reconsider, seriously.