OR you can simply project the fourth dimension into 2D, much like how we project 3D pictures onto 2D screens. Here's an example http://jakebian.github.io/hypercanvas.js/
It does take practise to be able to visualise 4d objects, and I agree that 2d projection example isn't helpful. I find it interesting to think of the 3d -> 2d problem that some people have, and extend it to 4d.
A child would recognize a cube since we naturally see 2d projections of 3d objects as it is. Likewise a 2 dimensional being could recognize a 1d projection of a 2d object (looking at the 2d object on it's side.) But would a 3d object projected to 1 dimension make any sense?