Start with two pallets. Try to get the exact same pallets and some pallets that are in fairly good condition. Also, try to find pallets that use 2"x4" construction for the middle board. The bench finishes at 48"x18".

Circular Saw

Drill

Lots of screws
Hammer

Chisel

Turn the pallets over and remove the bottom.
I did this with a chisel and hammer. I just chiseled around the nails and then used the hammer to pull them out. You want to remove the bottom to extend the spaces between shelves for bigger shoes.
Your pallets should look something like this:
Next, cut them both in half the width way. Make sure you measure so they are all even pieces. Measure twice!
Now, most likely, your circular saw won't cut all the way through the thickness of the wood, so I used a hand saw to cut the remainder.
You should have four equal sized pieces of the pallet. Stacked on top of each other, you get the idea of how the bench will look. At this point, decide which side you want to face front and the order you would like to stack the pallets. I had some ends that were cracked on my pallet so I faced them towards the back. Also, I put the best quality shelves toward the top of the bench because I figured you would see them more.
Now we need to reinforce the bench shelves to be strong enough to hold a person's weight. Measure the width of the pallet.Taking a 2"x4" board (the reason why the pallet needs to be 2"x4" construction) cut 8 pieces of the board into the width of the pallet (18 inches).
Starting with bottom half piece, attach the 2"x4" along the outside edges of the pallet, like below. I used screws to do this.
Turn the pallet over (this is your bottom rung) and measure the width of you two boards. The height of a normal pallet space is not tall enough for most men's shoes. I needed to expand this, so I did so by adding boards to the top of the supports.

You will need to measure the edges (the 2"x4" you just screwed on) and the width of your middle supports. (If using a 2"x4" pallet, it will be about 3", hence the milled board above.) You don't have to do this if you don't want to. I just didn't want any overhang, but you could easily center the height extension boards. Cut the boards down to 18" long, there will be eight cuts.

Each shelf also needs some center support boards, so I cut two center supports for each shelf and two end supports for each shelves.

You should end up with

6- 2"x4"x18" boards (2 were already used)

8- 2"x2"x18" boards

8- 2"x3"x18" boards (unless you didn't mill down the boards)

Here's my cut pile (and my son's shoes):

Next, screw your center supports into place:
Starting with the bottom shelf, screw the two 2"x3"x18" boards to the tops of each of the edges. (Note: If you plan on finishing the bench, this is the part I wish I would have sanded the bench. It was very hard to sand the bench once all the shelves were put together.)
Now, stack your next pallet shelf on the bottom. Use the pallet overhang to screw it in place to the shelf below.
You should have something like this:
Place your 2"x4"x18" side piece on the pallet overhang and then put the top 2"x3"x18" piece on the top of the ends. You are using your 2"x3"x18" to hold the side piece in place. You need to screw down the top piece (2"x3"x18") to hold the side piece in and to attach to the shelf. (Note: I drilled a hole and then screwed in the screw. I just found it easier and I didn't want to split the wood. I wasn't sure how the pallet would would hold up to just drilling a screw in.)

Repeat the process. I used very long screws because I wanted to make sure that the screw went all the way through the shelf, into the side piece of the shelf below.
You should end up with something like the picture below. (You might want to use clamps if your boards are bowed a little.)
Now it's time for the top. I purchased a 1"x6" pine board for my top. I didn't want anyone snagging their clothes on the rough pallet wood, so I thought the top should be smooth. Measure the width of your bench, in my case it was 48" (including the overhangs on the side), and cut your board into 3 pieces.
Place your boards across top of the bench (there will be gaps in between them) and mark your drill marks. I decided to nail on the top, to add sort of a rustic feel. I had some large roofing nails that I liked the look of, so I used them. I did drill holes part of the way before putting the nails in so I was easier for me and I didn't dent the wood.
You should now have a bench that looks something like this! Now you have to flip it over to add the wheels.
I added wheels to mine, to make it easier to cleaning under.
I bought these wheels from Amazon.com and they are suppose to hold enough weight for the bench. I am proud to say that this is the only step I had to ask my husband for help on. I can't lift the bench to flip it over by myself!

After sanding (for weeks), staining, and applying the polyurethane, the bench is finally finished!

The total cost: Pallets (free) + wheels ($18.88) + boards ($13.25) +Stain (free, already had it) + Screws & Nails (free, already had them) = $32.13

Not too bad if I don't say so myself!

In addition to the bench, I found plans for an above storage and coat hook organizer from ana-white.com. (Here are the plans: Ana White Entryway Storage Shelf with Hooks) I don't know if you have seen her site, but I am in LOVE with it!

It was very easy to build and cost about $25.

Now onto the next project, which will look something like this:
source

I am building a 15 shelf, 84" tall wine rack that should hold about 120 bottles of wine! One shelf is assembled already, only 14 more to go!