This post on /r/guitarpedals inspired me to build my own pedal board out of a cigar box. It was important to me that the box be able to close (albeit upside down) so that you could put it in a gig bag or something and take it with you.

The whole project as described here took about one hour to complete.

Step 1: Materials

Cigar box. These are easy to find on eBay and probably in many other places. I paid $6.50 for the box pictured here.
Industrial strength Velcro, 2" width. I use only the name-brand stuff on my pedal board, it seems like the adhesive is much more durable.
Gaffer tape, 2" width. I used black because I had it on hand but it comes in lots of other colors if you prefer.
Ruler – I found a metal ruler was helpful for measuring and ripping the gaffer tape all at once.
Decent scissors.

Step 2: Check the Size and Spacing

The example that inspired this project used just the box top as a pedal board, but I wanted a box that would close so that you could take the pedals with you to a jam session. In order to accomplish this, all of the pedals need to fit inside the box, with room for associated patch cables, with the box closed. The box must have a minimum inner dimension of 5.25" in order to fit a full Boss pedal because of the battery compartment screw. You may want to measure your pedals before ordering to ensure you get a box with sufficient size. For reference, the inner dimensions of this box were 9.25" x 5.25" x 2.25".

Step 3: Separate the Box Lid

Because (a) the box doesn't have a real hinge, just paper attaching the lid to the box, and (b) even if it had a sturdy hinge, you wouldn't be able to hinge the box open with pedals inside, you need to remove the lid from the box. This can be done by carefully sliding the scissor blade (or a knife / box cutter, if you have one handy) along the attached edge.

Step 4: Make Velcro "Latches," Part One

In the end, the box will live upside down (although I am pretty sure the industrial-strength velcro is strong enough that the pedals could hang upside down like Batman without coming undone), so we need a way to keep the box and lid together once there are a few heavy pedals inside.

My solution was to use yet more of the Velcro – there's always plenty around once you start making pedal boards – to hold the box together. It is very important at this stage to keep track of which side of the lid is "inside" and "outside." I messed this up a few times. On my box, "outside" was yellow with a blue border and "inside" had the pretty picture of birds.

Start to unroll the gaffer tape, sticky side up. Roll out a good length, a few inches more than the short side of the box lid. Measure 3-4" of tape and then set the short side of the lid down so that the tape is attached to the inside of the box and extends beyond the box lid. Make sure you leave a small margin between the tape and the edge of the lid to allow for any overlap with the box. Keep unrolling the tape on the other until you have another 3-4" on that side.

Fold the gaffer tape over on itself until the edge meets the box edge. The sticky sides should more or less overlap, leaving you with a cloth-like flap on either side of the box lid. Repeat the process at the other end of the lid.

Cut about 4" of loop-side Velcro (the soft part) and then cut that piece into equal fourths. Flip the lid over so that the inside is up.That is the part I messed up the first few times. With the inside of the box facing up, attach one strip of Velcro to each of the flaps near but not quite at the end of the flap. Be aware that, for whatever reason, 2" Velcro seems to be a small but noticeable bit wider than 2" gaffer tape, so try your best to center the Velcro.

Step 5: Make Velcro "Latches," Part Two

If you completed Step 4 correctly, you can place the lid on the box and the loop-side Velcro will be facing toward the box.

Measure out a length of hook-side Velcro roughly equal in length to the gaffer-tape flap. This will be longer than the loop-side piece attached to the gaffer tape. That extra length is important, as it will help the Velcro stay attached to the box rather than pulling off when you undo the latch. Affix the hook-side Velcro to the box underneath the gaffer-tape strap. Repeat for the other four corners.

You should now be able to close the box and get a reasonably firm seal.

Step 6: Prepare the Pedal Board

This step should be familiar to anyone who has prepared a pedal board before. Measure out a length of loop-side Velcro slightly shorter than the long side of the lid (again, leaving a small margin for the lid to fit into the box). Depending on the design in the box, you might want to cut down the width of the Velcro. The second photo shows a different box where I used the regular 2" Velcro at the bottom, but cut it down to 1" at the top, so the picture would still show.

When you have the Velcro to the length and width you want to use, apply it to one of the long sides of the box, leaving a small margin all around. Repeat for the other long side.

Step 7: Check the Fit

Put the pedals back on your board to make sure whatever Velcro you have on the pedal bottom is attaching firmly to the Velcro on the pedal board. If you used the full 2" width this shouldn't be a problem, but if you cut it down at all, and especially if you're using smaller pedals, you may need to make adjustments. On the other pedal board (see previous step), I found that if I used 1" of Velcro on both sides, the mini-size pedal wouldn't reach both strips – which is why I used 1" at the top but 2" at the bottom.

I didn't have patch or power cables with me when I was working on this, but it would be a good idea to get everything wired up at this point and be sure it all fits.

You should now be able to lower the box lid over the pedals and latch it with the Velcro. Ideally the box will stay closed on its own but open easily when you want to open it.

That's it! Time to plug in and jam :)