Your temperature gauge could be the most valuable tool you possess on the opener no matter what species you are after, water temperatures in some Northern lakes may range as low as 40 or 50 degrees.
This means you should look for the warmest water you can find. Even a few degrees can make a difference. Shallow bays with weedy or mucky bottoms, mouths of streams, man made channels, etc., especially those on the North and Northeast shores where the sun casts its heat at its zenith.
Wind plays a big part because it blows the warmer surface water around. Example: one side of a lake can be warmer if the wind has been blowing toward that side for a day or more. If you can pick the lake you'll fish during the early season -- smaller, shallow stained lakes will be warmer. Obviously, the lakes in the Southern part of the state will be warmer. Just make sure the lakes you pick have a good supply of walleyes. You can go on the DNR websites and get that information. I've been known to switch lakes even on opening day because the lake I started on was slow. That move saved the day on a few occasions. If you do not find the fish, you cannot catch them. It doesn't take a genius to find the warmest water you can in any lake.
Plankton and insects get active as the water warms up. They draw in the minnows which the game fish feed on. Until you find water at least in the 50 degree range, you must keep your lure presentations as slow as possible. Very small one-sixteenth or one-eighth ounce jig dragged instead of jigged vigorously can be very effective. If you find a concentration of walleyes, it is very hard to beat a bobber-leech combination. As the water temperature warms, you can increase your presentation speeds. As an example: trolling rapalas or casting crank baits of some kind--rapala's Xrap is one of my favorite presentations for casting in cold, shallow water for walleyes. This suspending lure is worked back to the boat in a series of glide and stop motions. The pauses between glides where the lure basically suspends motionless will be when the fish are triggered into hitting the lure.