Preparation
The Exhibition Theme
Is the exhibition open to the general public or just the trade? If it is for the public at large you need to entertain in some way: a very technical presentation will not appeal.
However by making your material very technical you can virtually select who will stop and be interested. But beware of the idle asker of questions — he may be a street sweeper who would never in a million years be a customer, but he just likes to talk technicalities.
From the very start find out what his position is. You will also be a magnet for 11-14 year old boys with technological interests: they will amaze you with their knowledge but will take up an awful lot of your time!
The more technical or specialised the exhibition, the less space you need to devote to basics and the more easily you can predict who (or what) your visitors will be. And with a specialised exhibition your stand design is much easier because you can be more technical.