For a small nymph pattern, that sinks quickly, it is hard to beat the Copper John. In smaller sizes, it will cut the surface tension and sink quickly. Use it by itself, as part of a multiple nymph rig or as a dropper below a dry fly/indicator set up. I have tied this with the traditional copper colored wire and the with black and lime green copper wire. Blues, reds, well there are many colored fine wires out there now in shops or online. Here is a nice S-B-S (step by step) at SwedneckFlyFishing on tying the Copper John. My advice: keep the Biot tail less than the length of the shank, and keep the partridge legs about half the length of the shank (both as depicted here).

Copper John Nymph at SwedneckFlyFishing.com