the knife blade at the same time. if using a paper clip, hammer the end of the paper clip to flatten it before trying to put it in the door.
you want to rake the pick across the keyhole pins. you want to be careful not to break the lock or the knife so you may need to carefully wriggle the knife for a while until you hear a click.
you could also try a credit card if you’re trying to get through a lever-type doorknob. just slide the card into the crack in the door, where the lock is, similar to the process with a knife. be aware you might ruin 