Trace around the electrical outlet face plate so you know where it hits on the wall. This line gives you a guide so you are able to lay tiles over that line so the edges are covered by the face plate.
Shut off the power source for the electrical outlets. Remove the face plate from the outlet. Remove the screws so you're able to pull the outlet out slightly -- it's easier to work around.
Tile the wall with whole tiles, starting the bottom row at the middle of the countertop. Continue working out from this point with all of your whole pieces; don't forget to space them properly. Leave space around the outlets if you aren't able to fit a whole tile there.
Measure the distance from the edge of the last whole piece to the edge of the cutout for the outlet. Allow for the grout line between the last whole tile and the piece you're going to cut. Measure so that the tile will go just beyond the outline for the outlet face plate so it is covered.
Cut whole tiles into smaller pieces using the tile cutter so they fit. Hold the tile piece up in its spot to ensure if fits properly without covering the cutout for the outlet. Make additional cuts if necessary to make the piece fit.
Attach the cut tiles in the correct spots around the outlet.