Do you crate your dog? I would crate her before having people in. That sometimes is the easiest because then you have already welcomed the person into the home and taken that chore away from your dog. If she is still strange then I would have the person sit next to the crate (not crowding or facing the dog) and drop treats inside.
If your dog has a good "stay on bed" then I would use that as your next step. Have the dog stay on the bed with the other person in the room and just click and throw treats for good calm behavior.
Teaching a go touch command can also be useful. Start with a good hand touch yourself and then gradually work up to clicking and treating for touching good friends on command and then you should be able to transfer that behaviour to people she doesn't know well.
"Never doubt that a small, group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has." - Margaret Mead