What I do is start at the left end, for example, of the roof and work across where I'd end up with an odd piece. Then I'd start at the RIGHT end and work my way across where I'd end up with an odd piece. This is assuming you had rafters 16" OC all the way across, from rake-end to rake-end.
Now, if your installation doesn't fit the assumption and your rake-end is, say, 13" from the 1st rafter, I suggest you cut your next-to-last sheet in half, and then put an odd-sized piece from the 1/2 sheet to the rake-end. Then, start at the end you finished on with a FULL sheet and work your way BACK to the the opposite end, and do the same with the 1/2 sheet and an odd piece.
You always want any sheet, whether it's an odd-sized sheet or not, to span 3 rafters, on the end. (4 rafters is optimal because at 16" OC, gives you 48" which is 1/2 sheet.) Start, for example, at the left end and lay 8' sheets until you end up with at least 3 rafters exposed (OC). (If you have to cut back on a sheet to get 3 rafters, do so.) Then, cut a sheet to fit the right corner. Now, start at the RIGHT end with a full sheet and work your way to the LEFT end until you end up with 3 rafters exposed (OC). So, you see, alternating 'ends' have an odd piece. You can't be too choosey on waste when it comes to structural soundness. If you have a piece that spans only 2 rafter, and you walk on it, you easily work the nails loose.
My best to ya and hope this helps. BTW, I suggest drip edge all around. Otherwise, the ends of your sheething is exposed to rain and the weather, thus shortening the live of the roof. I usually treat the ends with either primer or preservative before I put the drip edge on. Technically, whenever you cut a 4 x 8 sheet, you're suppose to protect the cut end since the factory only protects the 4 x 8 ends. 'nough said.