On any given body of water, knowing where you have been will almost always help you determine where you should be going.
There's no substitute for experience, but the same can't always be said for experiences. Sometimes, walleye anglers fall in love with certain areas or techniques that have been good for them in the past, and they overlook the current factors that actually dictate fish behavior.
We've all had days where a certain rock pile, point, sandbar or river bend has been loaded with quality fish, and it's human nature to try to repeat that bonanza. But just because you pounded the fish there in April a couple of years ago doesn't mean the walleyes will be there this year.
In fact, my personal list of phenomenal catches has included more one-and-done experiences than situations where I've returned to a familiar spot and repeated a great catch. I can probably list a spot or two that has been spectacular on every body of water I fish where I've never caught another walleye.
Of course, there are some exceptions and some spots that are always worth checking at certain times of the year when specific weather and water conditions exist. The important thing is that we don't get hung up on history and burn valuable time that would be better spent elsewhere.
More important than knowing where the fish have been is knowing why they were there in the first place. That's the type of experience that can be applied year after year as you try to determine a game plan for a current outing.
Usually, walleye location has more to do with seasonal migrations, forage, water conditions and weather than it does a "spot on the spot."
April is a month that can include pre-spawn, spawning and post-spawn walleyes. Water temperature factors into what stage these fish are in, but other criteria contribute to triggering the spawn, as well, including the length of the photo period. 
Let's say it's been an especially cold spring when the water temperature hasn't climbed past the low 40s. That's colder than what is generally accepted as spawning temperature.
If that's the situation in early April here in the Midwest, we're probably looking at mostly pre-spawn fish. Then we can develop a game plan accordingly, singling out likely staging areas in the vicinity of established spawning habitat.
If it gets to be mid- or late April with those conditions, some female walleyes will force the issue rather than wait for things to warm up. While most areas in a lake or river remain cold, a walleye can increase its body temperature and accelerate the spawning process by moving into shallower, warmer water.
When that occurs, it probably means it's going to be a slow, extended spawn that lasts for a couple of weeks. We'll want to poke around in the spawning areas during lowlight periods of the day, then work on pre-spawn fish the rest of the day.
If it's a warm spring and the water temperature climbs rapidly, it could be a quick spawn where the majority of the walleyes get their business done over a short period of time. Then we can concentrate our efforts accordingly.
Modern electronics and mapping have made the challenge of locating these fish a lot easier than it was for our angling forefathers, and my Mercury-powered Triton 215X makes it quick and easy to get from one spot to the next.