I wouldn't call myself an expert, but I do spend a lot of time fishing for lake browns. In general I agree with a previous poster; browns are very bass-like in their feeding behavior. But I'll try to throw out some general hopefully helpful tips.
It's hard to be specific with advice without knowing what prey items are in the lake, among other factors. However, if you can find out if there are crawfish in the lake, that's almost all you need to know.
If 'dads are present, then browns will eat them. And spring is a good time to fish any pattern that resembles a crawfish. I believe browns focus on 'dads in early spring because that's nearly all there is to eat at this time of year. there aren't any bugs yet, and baitfish are probably pretty hard to catch for sluggish browns. Crawfish on the other hand are easy prey and pack a lot of calories for a hungry fish. In my own experience, I've witnessed big browns in a 7-10 foot deep cove cruising the bottom sucking up baby 'dads about one and a half inches long.
The color for early spring is a brown with green fleck, such as a brown crystal wooly bugger. 'Dads in early spring come out of hibernation close to this color pattern, and darken as the year progresses.
Browns also like their prey to move. Of course this is not always true, but it's true so often that I always start by inducing some movement in my flies when fishing for browns. So don't be afraid to strip your flies once they get down to your target depth.
Without knowing anything about your lake, I'd suggest trying to fish between 12-25 feet at this time of year, assuming that there are crawfish present. This means finding structure in your lake at these depths. Crawfish love gravel or rocky bottoms, especially at the base of steep cliffs or anything that drops quickly into the lake. If your lake has a dam, fishing along it should be productive.
If crawfish are not present, you need to find out what prey items are in your lake, besides baitfish. There has to be some prolific food item the fish can eat without expending large amounts of energy, such as snails, freshwater shrimp, etc.
Once you get a few fish to hit, you can start patterning the lake and figure out how to get into the pig fish.
Here's one of the 27 browns I caught last spring using a modified brown crystal bugger: