I've made two types. Firstly, I made one where all the squares were the same size and I just sewed them together. I made a little pattern on the diagonal with the colors of jeans....looks kinda neat. I didn't have a problem with meeting the seams. I pinned them like I do regular cottons. I used a thin bat, and tied it with flannel backing. The second one I off-set the seams by creating half-blocks and then none of the seams had to match. That was much easier piecing-wise, but I think I would have liked it more if I played with the colors a little.
Using jean thread and jean needles are a must. I ruined a good machine not using an appropriate needle. I won't make that mistake again, it cost me a lot of money to get my machine fixed.
I plan on making another one as my dear uncle died and my cousins couldn't believe that all I wanted was his jeans. They were glad to be rid of them. Little do they know....I plan on making it again like the first one just with squares.