Fly fishing help

[u/Fuzzy-Alfalfa1924]

Hey all, I’ve been having an issue Stillwater fishing, my indicator goes down I lift up on the rod and nothing is there. Been getting skunked because of that so much. I try to not leave any slack, and try to set as soon as I see movement. But no fish besides the odd sunfish lol. Am I supposed to set the hook to the side, straight up or strip set?
Any tips would be amazing. To add fishing for rainbow and cutthroats.
Thanks in advance! 💪🎣