I completely agree with everything Txredraider said.
I sometimes use a fluro line as the "Tippet" if I want to get a light fly down a little deeper a little quicker.
One cheater method I also use is something George taught me for marking fly line weight. At the shooting end of the fly line, he makes a wide mark with a marks-a-lot, and then several thin lines to mark the fly line weight. One thick line equals 5#, and then each thin line equals 1#. So, one thick line plus 3 thin lines equals 8# line. One thick line plus one thin line equals 6# line. This makes it easy to tell what the fly line weight is if it's been taken off the spool. What it also does is act like a strike indicator for light bites. I may not feel the bite, but the stripes make it easy to see the line move if a fish runs with the fly.
Clear as mud?
