The items on this stool(Ebby's window perch)are what you need to make a crocheted rug. That, and the ability to crochet. Pretty hard unless you know how. See the 'strings or threads' on the scrap of fabric? Pull all of the loose threads like that off your fabric strips. They really complicate the process.
This is my tried and true method of joining up my fabric strips. I layer two of them, both are right side up. I overlap an appropiate amount, stitch, doing a anchor stitch(forward and back), then across the 1/2 to 5/8" pieces, another anchor stitch and on to the next pair. It's chain piecing ala 'strips'. Snip apart, and then trim off the access fabric on both sides. It's putzy, but good tv work, or when yakking on the phone. A no-brainer. Roll into balls and anchor end with a pin.
Now you can crochet, for practice or for real. The book calls for a K hook, and I find that to be a good size for the fabric strips I've described. You can go as big or as small with a hook as you choose. A big hook and narrow strips will give you a fairly AIRY piece. For narrower strips, a smaller hook works well. For wider strips, I recommend at least L or M hook. They come in plastic and metal. Make a loop, with or without a knot to anchor it. Lately I've had trouble with my loop pulling open and I've started doing a knot. That can be removed later, or stitched down as part of the center.
Chain 6, and when I say "loosely", I mean LOOSELY....you are going to be putting two(2) single crochets in each of those chain openings. It gets crowded fast!