here's one I prepared earlier:
https://forums.mtbr.com/scott-sports/twinlock-replacing-grips-987849.html
In short, you need the plastic bit that should come with the bike, or get one from where the bike came from. I did a bodge of wrapping electrical tape around the bar till I got the doodad, it worked OK but looked crappy
One thing to notice as well, at least for my bike, they use the teeny tiniest Torx screw they could find, had to go buy a tool to fit it and because its so incredibly small and crappy, I stripped the Torx-head-ness out of it and had to steal the bolt out of other grip (I was doing loads of setup changes, swapping bars and grips a bunch till I got a setup I liked, so tightening/loosening a lot).