Add mortar onto wall as shown.
Place mosaic onto wall by holding the top corners insuring to keep as flat and straight as possible. Try not to let the mosaic bend as this could cause chipping of the tiles.
Carefully float the tiles onto the mortar with just enough pressure to adhere the mesh onto the mortar.
Add your surrounding tiles or trim with pencil trim or any other trim you like.
Let dry according to mortar instructions.
Add grout (Mix using instructions on grout bag).
Can use a float or just apply by hand.
Finish project by sponging off grout.
(Repeat this process until no residue is visible).
You can use a small brush to remove as much grout as you need from around pieces that are lower than the circles.
Entire project only took a few hours to complete. Very DIY.