The easy way to make an M is to simply make an E and lay it on its side. Take a look at my quilt Star Light to see how that looks, it's back in July's archive (I think).
If you want angles, start by making a small V or a large narrow one. I started with a small V cut so that the legs of the V end on the sides rather than in the corner or the top of the section. (That has to do with where you want this bit to meet the side of the letter - I have made some M's where the middle bit has ended up detached from the sides and I don't like it so well.)
After finishing up the V portion, I added some background at the bottom
and a wide strip on the left and a medium strip on the right. I present, the M.