EQ (Electric Quilt program) is my best friend. You don't have to get the latest version. There are a lot of us that are still running EQ5. Is that a dog or a cat in the center of the quilt? You yardage will depend on the amount of prints you find. I would buy 3/8 of a yard. There are precut 5" squares called charm packs. Easier way to get a variety of colors but you pay a bit more. You might want to search for some Robert Kaufman's charm especially if you want to use a particular color such as green in the quilt you posted. Good Luck.