Step 3 - this is something I came up with for beginners because the question always comes up about "how big do i cut my pieces?" So I measure the front of the pattern and add 1 inch to that measurement. The pattern is the size the finished block will be so you will have to add AT LEAST 1/2 inch for the seam allowances. I find that adding 1 inch gives you plenty of "playing" room.
I usually also print out a copy of the pattern and jot down the sizes of pieces I will need and take it to my cutting table.
My estimate for sizes for this block would be as follows:
center rectangle - 7" x 4"
small corner triangle - 4" square cut on the diagonal
big corner triangle - 6" square cut on the diagonal