Good post Appy.
You want to learn to balance your upper body with lower body, and not using hands/arms to cling on in attempts to keep yourself on top while in a canter. Just hardly works well. You want to strengthen and learn to keep balance through your seat and legs and also learn the rhythm of the canter movement to stay in sync. Otherwise you'll end up being a sack of potatoes, which wouldn't stay on for long!
Don't know if you have any Pat Parelli info, his wife Linda (also horse trainer and riding instructor) explains horsemanship and balance from the inside out extremely well. She may have some youtube links to check out. You might surf there. There are plenty of good trainers with helpful insights, this is the first that just comes to mind. Watching someone else will help you also. You don't want to start off in the canter though, you need to learn to strengthen and balance through the walk and trot first.
Do you have a riding instructor or friend/relative that is an experienced rider?