Step 1: Wear a suit of armor
Literally. A suit of armor will protect you from the harsh world and make you look intimidating.
But don't just stop at a suit. Add some armor plating to your car, your house, your kitchen. The more armor, the more human you'll be.
Step 2: Practice your "human" expressions
Mirror, mirror on the wall, who's the most human of all? Stare into that mirror for at least an hour a day to practice your "I'm a functioning member of society" face.
Don't just look at yourself, look at others too. Observe how they walk, talk, and eat their food with their hands. You can learn a lot by watching, but don't get too close. They might get suspicious.