A tungsten jig Mop fly in orange from Solitude Fly. The tungsten bead and jig hook drive it deep and ride snag-free, while the bright orange mop body triggers strikes.
Fish it subsurface near the bottom under an indicator — an effective attractor in high or off-color water.
Adjust your indicator depth until the fly is riding just off the bottom, where nymph-feeding trout do most of their hunting.