First ... decide what you want to do then pick up some scrap fabric and scrap batting ... 9" or 12" square will do ... and PRACTICE!! DON'T TOUCH THE QUILT until you've practiced each type of stitch that you plan on doing ... even if it's straight line stitch in the ditch (in which case practice on scrap fabric that has been pieced - not a single piece of fabric). Stitch in the ditch sounds easy ... but it's not for everyone.
that's a very pretty quilt and you would be sorry if you used it to practice on and your skills were not up to snuff.