Hopefully it is not too late to reply to this...
I spend most of my time fly fishing nymphing. I enjoy catching fish a little more than watching lint float, and most of the time nymphing will out produce dries or streamers.
Here are a few things to consider.
Number one, if you really want to learn to nymph, don't take dries. Leave the box at home. Dry-dropper fishing is super fun and can be very productive, but it is tangential to learning how to nymph. When I first started fly fishing, I was hitting local hatches (Colorado) with dries and having some pretty good success, but a coworker showed me pictures of some nymph-caught giants, and it got my blood up. So I started nymphig 100% of the time, and it didn't take too long to get it together. You can't learn a new method properly if you don't commit to it.
Number two, don't try to cast nymph rigs. At least, not the way you cast dries. If you must false-cast, do it only once. Slow the casting stroke W-A-Y down and keep a big, ugly open loop. It will save you days of re-rigging. Roll casting (and water loading your back cast if needed) are the only two casts you will need about 95% of the time.
Number three, get a longer rod if it is practical to do so. Nine footers are standard, ten or even longer are good. Don't rule out a switch rod. But remember, you want one with a soft and supple tip. Power in the mid-section will help control surging fish and turn over chunky rigs, but the soft tip will assist in tactile bite detection (more on that in a moment) and protect light tippet if you need to use it. Small flies don't seem to be de rigueur in Oregon, but when they are called for it won't do to be using 3X tippet.
Four, use a longer leader. This will raise some eyebrows, but stay with me here. Tapered leaders are designed to transfer energy efficiently from the fly line to the fly. This makes a lot of sense if you are casting dries, as you want to lay them out nicely, and deliver the fly with accuracy. Nymphs are made to drift at the mercy of the currents, and as long as you can get the terminal of your rig into an area about the size of a hula-hoop on the beginning of the drift, you will be able to correct placement issues with the rod through direct manipulation of the rig or through mending. A progressively stiffer (tapered) leader is not very helpful in nymphing, and indeed many experienced nymphers feel tapered leaders are a hindrance. Who are the best nymphers in the world? The Europeans. They don't use tapered leaders, and neither do I, usually. A long (up to twenty foot) piece of 8, 10, or 12lb. nylon from my butt section or fly line loop is connected to a short "step down" piece of lighter mono, then to my tippet. Stay with me here.
A long piece of lightish nylon (not fluorocarbon, nylon) will just swirl and dance in the current as pretty as you please. The stiff butt section of a tapered leader fights with the water, but mono will go with the flow. Micro-drag is one of the biggest causes for refusal from trout, day in and day out. How many times have you seen a fish zero in on your bug, float along with it for a bit, and back off? You think they decided at the last minute they didn't like the color or the brand of dubbing? They didn't like the way it was moving. My 2¢. So get a long leader and go with the flow.
Five, learn to nymph by feel. There are certainly times and places for bobbers (aka "strike indicators"), and I carry several styles, but whenever I can avoid using them, I do. Unless you are on a perfectly flat piece of low-gradient spring creek with a perfectly flat laminar flow, indicators must be constantly adjusted. Fish this bucket here, move the bobber. Fish that seam there, move the bobber. That riffle? That cutbank? See where this is going? I noticed a long time ago that keeping your hooks wet is the surest way of hooking fish. If you are fiddling with your rig, you are not catching fish. I fiddle with my rig a ton, adding or removing putty weight, or pulling snot-grass off my bugs. Anything I can do to cut-back on the rig-fiddling will keep my flies wet and get me more fish. But there is more to it than that. Direct manipulation of subsurface flies can add an element of attraction. Gear guys call it by another name: jigging. Now I am not saying to sit there and jig the bugs all day, but a little twitch here and there, a little lift now and then, will work wonders in provoking takes. Trust me.
Six, diversify your methods. By all means, learn to western style high stick with bobbers. Then, also learn to French, Polish, and Czech nymph.
Seven, use your eyes. Almost all the fish I catch when I am nymphing I see before I cast to. My eyes are terrible, I am not Captain Eagle Eyes or anything. I just take the time. Seeing a fish is about the surest way I know to prove to yourself that there is a fish there to be caught. Seeing a fish gives you so much information. I like to use the fish as my indicator. If I know my bugs are in his kitchen, and he eats something, well, I am not the smartest guy in the world, but I can do that math. Set to the fish and you will have a lot more success than if you wait for the bobber to give you permission.
I guess that is about all I got for now.
Cheers.
SS