I just returned from a couple of days in Chelan. My mother's kitchen had twenty-two feet of wood molding where the wall met the counter. The section behind the sink was beginning to look moldy and unclean. That's uncool in my mother's world. She pointed out to me that I hadn't written about tiling my own kitchen and she needed information on how to do her's. My mother is amazing and can do quite a lot at 85 but I told her I'd help her with the project if she would go buy the tiles she wanted to use. When I arrived at her house, she had the work space cleared, the molding removed and the nail holes patched. She was ready to start. I am not a professional but here are the steps I followed and the things I learned in the process.

Have plenty of mastic and grout on hand. More is better...you can always return unopened containers and unused tiles but stopping in the middle of the project to buy more can be a problem.

Have extra tiles. Cutting around outlets may take a couple of tries.

Tools and Materials:
Tiles - measure linear feet X 12 = linear inches ÷ by tile size (i.e. 4") = number of tiles needed for one row.
mastic to glue tiles to the wall
grout to fill in spaces between tiles
sealer for grout
spacers
manual tile cutter - rent one from the local rental store. It makes nice straight cuts. I'll go into hand held models later.
hacksaw with diamond blade
plastic applicator and putty knife
grout float for apply grout
sponge
bucket
wide painter's tape
ruler or square
pencil
straight blade screwdriver

Step-By-Step:
Clean walls and fill any holes with patching material.
Tape off the area to be tiled.
Draw around the outlet or switch plates as a guide for cutting tile.
Remove wall plates for light switches or outlets.
Determine where you'll start and where any unique tiles will be placed.
Apply a 1/8th layer of mastic to the wall in small sections using the notched edge of plastic applicator.
Place tile onto the wall pressing into the mastic.
Use a spacer if you are going to place the tiles further apart rather than right next to one another.
Wipe off excess mastic with dampened sponge.
Allow to set up per the instructions on the container of the mastic being used.
Apply grout to small sections at a time with the grout float, wiping off with a damp sponge as you go to push the grout into the spaces between the tiles. Use unsanded grout for narrow grooves and sanded grout for wider grooves.
Let the grout set before wiping off any film from tiles.
Apply a sealer to the grout to protect from water and stains.
Remove tape and reinstall wall plates.

Here's how I handled the tiles I was going to have to cut for outlets, switches and spaces less than a full tile.

I started under the sink with the tiles that would span that distance putting the cut tile in the center.

I worked from the outer edge of the counter up to the cut tiles under the window installing all the tiles that didn't need cutting. I then determined how many tiles I needed to cut for around the switch and outlet boxes and corners. Those I cut and installed after all the full tiles were in place.

My mother is pleased with the way the tiles look and the bright clean appearance. The tiles behind the stove were an addition to the original design but makes cleaning the wall so much easier.