In order to stop liking someone, you need to get some space. As much as it might sadden you to stop seeing this person, spending constant or regular time with them is going to make it much harder to get over them. The constant stimuli and new experiences with them will just keep reminding you of why you like this person so much or even bolster your feelings, and it’ll give you more “moments” to replay in your head.
Cut the fuel at the source. As much as possible, try to spend less time with this person. If you can’t fully avoid them (for example, if they’re a co-worker, classmate, or part of a friend group you see often), keep your distance during any time you’re sharing space. You don’t need to be rude or completely ignore them, of course, but keep conversation to a minimum and try to avoid any one-on-one time together.