Well it shouldn't matter to them or you if you truly love him. So just be normal. They love you and wan't you to be happy so go for it! Hope that helped (^_^)
It can be very difficult unfortunately. Not to put you off or down, but I value honesty and I go by this principle.
The first person to speak to is the one your most close with, ideally a family member. Also, be sure that "he is the one", is he or his family going to accept you? Due to religion or cultural differences it can be a big issue on both sides. Speak to him. Make sure, and don't jump the gun. Perhaps speak to his mum, in other words, see if you could build a bond between you and his parents before even trying to convince your parents. I hope this advice has helped. May God ease it for you both.