To make it easy you need a vice, double sided tape and paint thinner.
It is not difficult if you have the right tools. Cut off the old grip and clean off the old tape. Put the new tape on. Pour some fluid on the tape and a little in the grip and shake it so the entire inside on the grip gets wet. Now slide the grip on in one motion. If you stop part way it will stick and you will have a hard time getting it back off. Make sure it is straight and you are done.