Look for lakes with lots of cover (weedbeds etc),you will usually find perch in these areas in the spring,summer in various depths.You will also find larger perch in schools of Walleye in some lakes.I was surprised the first time I spotted 2 large perch on my aquaview in the summer travelling with 4 walleyes.
I used to fish for perch in open water a few years ago and i caught them like crazy with just a #12 hook with powerbait, minnow, corn, eggs, you name it and i was in only like 3-6 feet of water but it was really weedy.
I like to use a smaller jig head tipped with Meal Worms. I haven't found anything that works better when targeting Perch from shore around Medicine Hat. Small Jigs work as well. Found most perch prefer a slower action by slowly bounceing the bottom. I usually let the jig sit for roughly 2-3 seconds on bottom before slowly lifting the jig. Depending on their mood you could have one every cast.