How can you inhibit crystallisation of hot superconcentrated magnesium sulphate I’m trying to create a gel like solution of primarily magnesium sulphate heptahydrate or Epsom salt and water.  It’s simple to create a hot super concentrated solution but when it cools it’s obviously begins to crystallise. Continuous stirring as it cools and cooling quickly creates a slush of tiny granules which eventually settle to the bottom of the solution like sand in water if too thin. 

How can a thick concentrated smooth liquid be created? 

I’ve looked into ways of inhibiting crystal formation but no good examples.  Maybe an impurity if some kind and then possibly a thickener if the mix is still watery.
First, your question involves inorganic chemistry, not organic, unless you're talking about the unmentioned gelling agent.

Second: Impurities serve as a source of nucleation, and stirring increases crystallization. If you leave the supersaturated solution in a clean container and allow it to cool slowly, e.g. in a Styrofoam cooler chest, it may take a long time to form crystals. If you use some thickener, such as PEG or gelatin, it might take longer yet. Left undisturbed, though, supersaturated $\ce{MgSO4}$ can persist for years. There are videos of it crystallizing after a seed is added.