Step 5: Cut out the tiles
Run the Cricut! The tiles should pop out cleanly; if they didn't, you need to set the cutting pressure wheel a little higher.
If you don't own a Cricut, cut them carefully with a guillotine, and perhaps round the corners off with a craft corner cutter, however the Cricut will cut them to the exact size of the Scrabble tiles, including the rounded corners.
(The Cricut is a great tool for engineers, even though for some reason it is primarily marketed at ladies for making birthday cards etc)