Pepsiboy

I would like to use my long arm quilting machine to "Stitch in the ditch" on a 9 patch square. Where on the 9 patch would I start, and how would I go around it to finish and not stitch over any of the seams more than once? I have tried to figure it out, but I always get at least 2 or 3 lines that are stitched twice.

Thanks, in advance, for ay help given.

Dave