Depending on the light conditions and the color of the water I try and use a high viz color. Bright yellow is my go-to, but I also use bright orange. I can watch both well as I’m drifting to make sure the line is “mended” back up-stream, so it doesn’t drag the float faster then the current. In murky water I prefer the yellow line, in clear water I prefer the orange line. I think the orange line is less visible to fish holding in shallower pools than the yellow. With both I use a fluorocarbon leader at least 20” long up from the hook…God bless you.