I would not FMQ this beautiful first quilt! It takes a while to get the hang of it and you really don't want to practice on a real top. I would just quilt diagonal lines thru the squares from corner to corner, extending these lines right thru the borders (use painters tape to get the line extension true). Don't know how big your squares are, but you need to read the info on the batting package. that will tell you how far apart your quilting lines can be. If quilting corner to corner thru the squares is too far apart, then just add an additional line of quilting in between them.
Oh, and if you have a walking foot, now is the time to use it. I would find the center of the quilt and quilt 4 lines radiating out from the center, making an "X". This will stablize it , then work on additional lines of quilting, from the center lines out. These can be from edge to edge.