I wanted to create a stand to organize my Green and Blue bins within my garage so that it would take up less floor space. A friend of mine's dad made one forever ago and I thought it was a great idea to make the same for my house. By no means am I a carpenter or expert. There are lots of ways to build this (probably better ways too) however these are the steps that I took to build it.

Supplies

2x4s - I had a number of spare from previous projects that I was able to use
Plywood - I used spare that I had from a previous project
4 deck blocks - extras that I had from my deck build (Found here)
Screws
Drill
Level
Measuring Tape
Table Saw

Step 1: Determine Size Needed

For this step, I just placed my biggest blue bin on the floor and spaced out the deck blocks to give myself enough space to put the blue bin in without hitting the sides

Step 2: Measure and Cut

After figuring the size of the floor layout, I measured how tall I wanted it and made a mark on the 2x4 to show the lowest that I could have the 2nd shelf (basically enough clearance to pull the blue bin out)
I cut the 2x4s to size (measure twice and cut once)
I placed the 2x4s standing up while laying 2x4s in the slots on the deck blocks to get my frame. Screw these into place (I used 2 screws for each joint)
After I had the main frame together, I took my spare plywood and cut myself a shelf.
Used screws to put the plywood into place.

Step 3: Add 2nd Shelf

For this step, I just measured the distance between each post and cut accordingly.
Use a level when adding each piece
I used 2 screws for each joint
I used spare plywood and added a second shelf, screwing down in multiple places

Step 4: Final Product

The plywood that I used for the 2nd shelf was a little smaller than the one underneath it, and I did not want to cut away from a full sheet of plywood just for this. It turns out to work in my favour, as we use this gap to dump stuff in the blue bins without having to pull it off the shelf