All you need is a scroll saw (I used my dad's new Craftman Scroll Saw to do this and it was so much faster than my off brand scroll saw) and a block of wood.
If this is your first time using a scroll saw then you might like to read step 2, if not then just skip it unless you might want some helpful tips on cutting. I like to sand all of my cubes and stain them so if you dont want to do this just disregard
Important: I will shortly post a picture of my sanded and stained cube.
Step 1: Selecting your Cube
The largest size my scroll size will cut is a 2in. cube. Its best to start with a plank of wood thats the size of your cube. Make sure you dont get too big for your scroll saw or you could seriously mess it up, the very action that the saw that uses to cut makes it get smaller than you think.
Step 2: Using your Scroll Saw
Next when cutting your curves it's best to push the cube into the blade then pullback and turn the repeat until you're done.
When you are cutting strait lines you might will want to try and push the cube into the blade and go faster, this not only can break your blade but it makes it so your cut inside the cube is not perfectly up and down because your blad will bend so you can only slide the cube parts together one way (this can be fixed with alot of sanding).
The last is don't try anything your not ready for, just be careful and keep track of all your fingers.
Step 3: Cuting the First Side
Step 4: Cutting the Second Side
Step 5: Staining and Sanding
The best way to sand a cube is to use a pad you would usually use on a machine but just in your hand make sure you are careful not to over sand anything or the pieces will not look good on the outside.