Here’s how to put a new hand grip on a bicycle.
To remove the old grip, you can just cut up the middle with scissors and pull it off. If you are trying to take it off and save it, then that’s much more work.
The secret ingredient for this is rubbing alcohol. If you put rubbing alcohol inside of the grip before slipping it on, then that will lubricate it and make it slip on easily. Then it will quickly evaporate, leaving the rubber to stick on to the handlebar. Other quick evaporating substances will work well for this too, such as nail polish remover, hairspray, or hand sanitizer.
Make sure the handlebar is cleaned and dry. Then place a little bit of alcohol on the handlebar itself and little bit inside the grip. Then just slide it on and put it into the position that is most desired.
If there are brake levers on the bike, loosen and move them over first, then install the grip and move the brake lever back to the desired position.
Give it about a half hour to dry or quicker out in the sun, and you are ready to ride.