Here’s the shortest path to a set of closet cubbies that I was able to deduce.
Step 1: get a big old 4×8′ piece of plywood and cut it up into a bunch of squares. Measuring helps, but for the adventurous types is optional.
Next, route a bunch of grooves for the shelves & divider.
Now, paint up the inside facing bits.
When the paint dries, start to assemble the box by joining the tops & sides into two L-shaped pieces.
Then join the shelves and divider, giving it the hammer as needed.
Now nail the box together!
Make a back for the thing to nail into the studs of the target wall. Oh, did I mention to leave a recess in the back of the box to inset the back in? Go back and do that, too.
Back to the box – put some molding along the front edges to conceal those ghastly plywood edges.
The box is now ready to be anchored to the wall.
And finally, paint the remaining bits.
And voila! Closet cubbies.