One of the most effective colors in my fly tying arsenal is this: fluorescent orange.
That color has worked wonders at the Farmington, Millers and Westfield East Branch rivers. I work with UTC thread to incorporate that color into some of my nymphs. Easy to do so.
Here is a great video at the Orvis blog. It shows how to tie an October Caddis larva pattern that also incorporates the thread color I had mentioned. I think having some fluorescent orange flies is always a good call, particularly in the autumn, when brookie eggs and October Caddis larvae are in the drift.
I hope this fall that I can meet this fish again–or, a twin of his.