Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4945667.
Designed to keep your fingers busy. It can help distract you from feelings of stress and anxiety, or simply something to occupy your mind. There are many mechanical fidget cubes, which are excellent, but tend to be squeaky, rattly and prone to wear. This simple type of cube is easy to carry around and use without causing distractions for others.
I have a direct drive setup and am able to print using TPE which is excellent for this type of object. If you cannot print TPE, then TPU is a good substitute. The best infill is a simple one, such as Zig Zag at around 10% to give a good amount of squish.
If you don't have access to those filaments, then simple PLA is fine and will give a good tactile feel.
Orientation in the STL provides for a support free print. If you prefer a smaller or larger cube, just resize to your needs, but I'd suggest printing the one at the size provided first as it sits nicely in the hand.