The first fish I ever caught on a fly was on a scud/nymph looking thing I tied up after watching another instructor (I was teaching tying) show the boys about bugs. I saw one on the bottom of a rock and tied a fair approximation and proceeded to haul the brookies in hand over fist. Cast out, let sink and strip back in with short strokes. You don't need an indicator. The fish will tell you they took it.
This fly is almost stupid simple.
Use whatever hook you happen to have in a 12-14. Straight, curved, whatever.
Olive Thread
Olive Medium D-rib
A few turns of olive hackle of some sort. Just something to look leggy.
A bead to help it sink if you want.
I now teach this to the boys up at Scout Camp because the brookies in Tumblesom Lake can't leave these alone! I have seen boys catch fish on their first cast with these! The first time I used one, they had to drag me away from the lake kicking and screaming to teach the next batch of boys!