I have used flip and stitch methods for some of the more angular pieces, applique methods for the more circular shapes. Is there a "theme" to the crazy quilted table topper? You can use a felt batting and cotton backing<Most of the more recent felt dyes do not run like those made when I was a girl.> The felt protects wood table tops nicely and helps the coffee cups not to tip. Also, I find it stabilizes nicely. I take it also, that you are not thinking of beading and bulky embellishments, although, you can find places for them in the middle of the table if it is not usually used for placing things. Give yourself a little time to think what you will be placing on the table and what areas will not be used. It is fun to use those fancy embroidery machines to do fancy work that can be placed here and there. Most of my stitching is hand work so I will leave the suggestions such as what type of patterns to use to those who do machine stitching...but most of all - enjoy the process!!! I suggest going to Google and hitting the "images" word in the upper left hand corner and putting Crazy quilt stitching in the google search bar - you may even find my favorite Crazy quilting blog -
http://www.pintangle.com Sharon does amazing work with embellishment.
And most of all - PLEASE let us see YOUR work!!!!