The best way to do irregular shapes is to cut them up into shapes you know like rectangles and things of that matter. Using the measurements you know. You can figure out the long skinny rectangle, on top or in the middle. This attachment isn't the BEST example but it shows that sides, and using those measurements you can cut it up into 3, 4, maybe 5 shapes, whatever makes it easier for you. :) I hope this answered your question.
