Brett Jensen, fly designer, has this to say about his Obie Skater:
The performance of the Obie Skater clearly comes from the 2mm foam lip tied right behind the eye of the hook. The hair wing adds support and helps to strengthen the fly's stability. I tie this pattern both with a short and a long body. Both patterns fish well. However, I find the short body pattern is best suited for traditional tail outs or holding water that is soft, slow and smooth. The long body version of this fly fishes best in situations such as, a soft slow rolling riffle, or perhaps, one with a delicate and gentile surface chop.
Materials used to tie this pattern are simple, easy to find and the pattern itself is straightforward and easy to tie as well. For the body material, I really like UV Ice Dub. This dubbing is available in several colors and when spun in a loop you can easily control its thickness. Don't spin the loop too tight. I like it with just enough give or softness so the ribbing pulls in just a little, and seats on a firm base. Before wrapping the body with the newly formed loop, be sure to take a dubbing needle and pick through the fibers freeing those that are trapped.
For the wing, I prefer to use elk, and finding the perfect patch can be difficult. This is not to say that deer hair doesn't make a good looking and durable fly, it does, and I use both. But elk, especially yearling elk, is a bit stiffer and flairs less. Whether you use deer or elk, closely examine each patch and select the one that best proportions to the size of fly your tying and look for the texture and hair length that works for you.
Be careful when tying in the foam lip. The first few raps of thread should be snug but not tight. You can easily weaken or even cut the foam if you overdue it. Once the lip is in place, you can then secure everything tightly with a smooth layer of thread. A smooth, even surface is easier to dub over, and also makes a good base for securing the hair wing. Body color and wing type are up to you. Be creative!
Hooks for this fly are important and aren't cheap! The short body Waker is tied on Gamakatsu's, Split Shot/Drop Shot hook. I love this hook! It features a nice wide gape and a very modest up-turned eye. Absolutely a perfect fit for this fly. The long body pattern is tied on an Alec Jackson Spey Fly Hook. It too features a slight up-turned eye, and is of high quality.
Are the Jungle Cock eyes an important element of this pattern? Probably not! A nice touch for sure, and they might stimulate a response. But the real attention-getter is the surface disturbance, and this fly creates a good one.
There is one thing I would like to mention and, I'm sure you have all heard this before. But, when fishing a waking fly, the grab doesn't always come at the sweet spot in the swing. Over the years, I have hooked numbers of fish when the fly has finished swinging and dangling straight down. It doesn't happen often, but it does happen. So, at the end of the swing, before you start retrieving, let the fly relax for a few seconds. Make this a habit. And pay close attention to those scant few seconds when resting your fly... especially when fishing the first light of early morning!