I knife [shft-K] them into bite-sized pieces. If you're not exact (and who is) then grab the snap tool [Shft-G] and correct those corners. No polys with more than 4 sides? Great. Onward.
	Hit the [tab] button. You now have a sub-patched cylinder. If this is what you look like, you're in luck! Otherwise, turn on symmetry and "onward"!
	Align the polys to taste. Work from one view first, like the front. Remember, I've got my background image for reference.

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A self-made man!
So, you've got in touch with yourself using various graphic utensils. Great! Slap that new-found knowledge up in the background projection of an appropriate window [ctrl d].
I'll start off with a cylinder primitive with 12 sides. I start with 3 segments, but we'll be cutting more in almost immediately, so feel free to start off with more if you find it faster.
Select the end polygons. They're both have more than 4 sides, so they won't sub-patch.