I made mine using store bought cube shelves, but you can easily build your own shelves and embellish them so they look like Legos.
You will need--
Shelves or wood to make shelves
closet rod or dowel, depending on the size of your shelves
ruler or tape measure
some kind of saw to cut your dowel--I used a chop saw, but you could also use a radial arm saw or a band saw, whatever is available to you.
wood filler or spackle
spray paint -- I used Kilz as a base coat and a bright Rustoleum gloss color for the finish
Note: this tutorial is written using an existing shelf.
First, you'll need to decide how many "pegs" will go on each side of your shelf. I just eyeballed what looked to be the right proportions for my shelves. For example, the shelves that are 8"X8" looked better with six pegs per side, while the shelves that are 6"X6" looked better with only four. It should be easy enough to see which looks right.
Count all the dowel pieces you'll need for the shelf. Take the closet rod and measure every 1 1/4", make a mark. You could also measure the same amount on your saw and set up a block at 1 1/4", it is a bit more accurate. Cut the amount of dowel dowel pieces you need for your shelves (this gets a bit tedious) and sand any rough edges.
Next, use a ruler (or carpenter square) to mark out where the dowel piece will go one side at a time. Then glue them in place. They might slip a little depending on how much glue you put on, not a big deal, just be aware.
Then, using a brad nailer, staple the dowel pieces in place. Use the wood filler or spackle to fill in the nail holes, and sand when dry.
Then, paint your new Lego shelves. I base painted mine with white Kilz spray paint first to help cover the dark wood and so that the whole self started the same color. I also think base painting with white makes the colors look brighter.
Then, hang them! If you used an pre-manufactured shelf, you can simply hang using the existing hardware, if not, hanging hardware is readily available at and hardware store.
Simple as that, you have functional and decorative shelves all in one. These can be made any length, width, or stacked together, really the possibilities are endless (kind of like real legos) So have fun with them!
Let me know if you make some! I'd love to see them!