I've had the left side off a few times, so I can tell you that you need to bend back the flange at the inboard end of the rubber grip on the rider side of the bar and you will see a bolt head. This is a small Torx, I can't tell you what size exactly but if you have a set of smallish Torx drivers one of them will fit. You need to withdraw this bolt completely to free the grip/wheel/switch assembly, but also have to remove the two cables that go into the switch block. There is a little cover which clicks off, but I found it easier to also remove the bottom half of the outer shell of the switch block. There are two screws holding this on but it also clicks into the upper half so you have to squeeze it a bit to split the two halves. You will then find it easier to remove the two connectors on the ends of the two cables. The smaller cable is for the power to the heated grip and has a 2 way connector. This connector seems to be just a friction fit so should just pull out but you can maybe reduce strain on the cable by using a fine screwdriver tip to help ease it out. The other cable has a a 6 way connector and has a latch which engages with the body of the switch, so you need to flex the latching tab to free the connector. Don't just pull it as you may damage the cable. I hope that helps.
Fred