When I say semi-random I mean that the tools this thing is meant to hold are not completely themes, which is to say some are for woodworking, others for the drill press next to it, and... well, I startet with stuff I usually needed for the drill press, namely wood drills and forstner bits. Next were the drills for stone and metal to have them all in one place, and the japan saw and the bevel gauge jumped onto the band wagon, and a collection of bits did, too,justifying it's presence with my long-standing idea of a wall-mountet holder for my cordless screwdriver. You can decide whether that qualifies as random.
When I say tool organizer, I mean that it allows me to place the tools in ithang them from it. It does not actually help me prvent the loss of drills or bits or any other tools places on or near it. Well, actually, it is qhat it commonly referred to as an organizer, so...
When I say scrap, I mean pieces of wood, leftovers and stuff you would not usually use except for such purposes. There you go, I think that sentence was just a fancy way of saying nothing you did not know already. Anyway, moving on...
Step 1: Materials and Tools
board(s) - I used a piece of leftover for the back and pieces that came with the packaging of some furniture (called particle board I think, and with fake wood surface, as well as parts of slats from an old bed frame)
Step 2: Figuring Out What Goes Where
This is where you look at the tools you want to store and the space you have (first the free space on the wall, then the designated back piece of your organiser). Figure out how to place them so you do not waste that prescious space, but keep in mind that no amount of room saves is worth being unable of actually getting the tools out afterwards.
There are, of course, several ways of storing tools, and far more than I can ever think of are described here on this site. What I did could easily be improves upon, and I do not expect the design to be finished - either it will fall apart because particle board does not lend itself to being screwes that well, or because I find new ways of adding clutter.
Step 3: Saw, Screw, Repeat
What I did was mostly freestyle - take a slat, mark of the length of the back piece with a pencil and have at it with the saw. I'm afraid I used a mixture of improvising and guesswork, figuring there were no marks for looks and style in my workshop. There usually are not. So I cobblet together two boxes and had some screws stand out as hooks for those tools that came with a hole.
Step 4: Done and Done.
Here's the finished product. Fixed to the wall with two screws and probably not too stable, I hope it will suffice. Questions, comments etc, you know the drill.