Hitting and Head-butting at 10 months

Please help! My daughter is 10 months old and she has been hitting and head-butting people. I've tried everything I can think of. Other than spanking or lightly hitting her hand because it's contradictory in my mind to hit a child to get them to stop hitting. She knows what the word no means but she laughs when we tell her and we've tried time outs and quiet time to calm down. Any other ideas on what to do? I am getting desperate. I don't want her to hurt herself or anyone else.