Fresh-water trolling is usually done with fishing equipment for standard bait-casting. A glass fiber fishing rod is well suited to this fishing method as it is very durable and unlikely to break.
If you have the standard type of reel, fully loaded with bait-casting line, it is OK for most uses with the exception of deep trolling.
As usual, small fishing lures must be used with light tackle while medium lures and heavy lures require medium and heavy tackle, respectively. Note that heavy fly tackle is useful when trolling for large trout such as rainbow and brook trout.
To reach different water depths, you can try out one type of lure with different weights, or you can go for testing out several types of lures in combinations with varying weights.
Spoons of the wobbling and darting types are excellent for trolling. Some may be trolled at both slow to high speeds and maintain the desired performance. Others work in a more limited range. You must fish them at a speed best adapted to their action. One can learn these things only through experience with specific lures.There's no cut-and-dried formula to follow.
Spoons and spinners of the larger varieties can be used to advantage when fishing for such species as lake trout or pike. Wobbling or darting spoons are my preferences, rather than those that spin - the spinners are more tiring to troll in my opinion.
Spinners pull harder in relation to their size than spoons, and big, round-bladed spinners are an effort to use on light tackle. Spinners have a tendency to twist a line, so when you are trolling with them, it is usually advisable to add extra swivels. Some spinners twist a line so badly that a rudder-shaped sinker or a plastic keel placed ahead of them will save you from much grief.
Once a line gets badly tangled, it is such a chore to untangle it that one is tempted to throw the line away. If a line is twisted but not tangled, take off the line-twisting lure and let the line out carefully behind a fast-moving boat or feed it into a fast current until it unwinds. If the line is tangled and knotted, you need patience, good eyes, and imagination to straighten it. A new line may be the best solution.