I've used mine about 3 or 4 times, so won't be much help but:
not sure how the colorline changes with conditions. The other two colors are for personal preference or lighting conditions. One is for night time viewing I believe, similar to the contrast function but easier I guess if you call going thru the menu to find the correct selection easier. Noise rejection and surface clarity are personal preferences as well, and lake/water conditions (muddy/stained/clear) as well. Adjust each one a bit at a time and see if you can see any change, for better or worse for where and how you fish. There are no set "guidelines" for adjusting a FF, most of it is personal preference to where you have some confidence in what the FF is showing you. If you know the location of some structure, hover over it and adjust the various settings to where it looks familar when compared to your old FF and go from there.
GO BIG ORANGE !
I meant to behave, but there were just way too many other options available at the time.