If the pattern is continued to the edge, you're probably going to have to do one less stitch on each end. Are you there yet, or just reading ahead? By the time you get to that point, you should be able to see which stitch goes on top of another and find your place in the pattern. Or you could make another copy of the chart and starting with the decrease rows, mark where the decreases are so you could see them on the chart. There are decreasing tips too, looks like some of the edge sts are in garter, so that would make it easier.