I have suspicion the mom is overprotective, how do I make a good impression?
Answer:
Shake her hand, that's one good action to start. Be a kind, strong, and clean, sharp person when you talk to her. Show that you're a kind person and that you're helpful and are very caring about your girlfriend, do anything you can for her and be sweet. :) Treat her mom like a lady and it will help enormously.
Answer:
give her mom flowers and then a kiss on the lips, that works really good if the girls dad is there, haha, jk, but for real, just be yourself
Answer:
Try taking your girlfriend and her mother out to lunch.
Answer:
Don't overdo. On your first meeting, give a firm (not gripping) handshake, be polite, and make eye contact (if you avoid eye contact it will seem like you are hiding something even if you are just nervous). and most of all Relax! Good Luck - let us know how it goes!