Sometimes I'll take a piece of yarn or crochet thread in a contrasting color and weave it through a few stitches because it's easier to see and know for sure just exactly where I meant for the marker to be. The yarn will stay in place but pull out easily when I'm done with it.
Cheating is an option. . . . Cheaters never win and winners never cheat, but smart knitters who want to retain an iota of sanity do, cheerfully. ~~Kory Stamper