How do you get out a striped screw?

Depends on where it is at and what type. You can drill it out and use a larger one in place of it. If it has any slot left at all, an impact driver might get it out. If it is possible to heat what it is in with a propane torch that will help. If the head is above what it is in, you can use a hacksaw to cut a new groove in the head. Cut the head off, take what it is in apart and grab the shaft with locking pliers.