About a year or two ago, I was fortunate enough to get my hands upon a Nostromo N52 gamepad, when the Tournament edition was still being introduced and slowly phasing out on the former. Well, it's still in one piece, so, if you're lucky enough to have one, or are planning on getting one, here's a little guide with a bit of help from other sources to make the best out of using it with the most buttons possible.
Here, in this thread, Grendalsh gives the new user a detailed guide via youtube on how to get the most number of buttons.
For the sake of clarity, I figured I'd help things along and create a diagram of what he basically has done.
Additional Note: The red button is used for Esc.
Notice how 1-9 are done in a square formation and that the last three buttons are put in the outside column? This leaves the three buttons on the right for the different states which would make four sets of twelve buttons. If you need that many, at any rate.
It should be noted that until I got this formation, I was always using my left hand's thumb for the jump button (0 on the diagram), and had assigned 1-5 on the red button and the rocker switch. However, I was still using keys 2,3,4, and 8 like I would the usual manner, but it would take up needed buttons. With this set up, it's easier to keep the keys you need to much closer reach. Though, relearning the muscle memory's gonna be a pain.
Next post, I'll show what I use for my UI, in hopes that maybe someone can get an idea inadvertently and improve on what they have.