Grilling jumbo prawns on the barbeque (on the barbie) requires a way to get them on and off without having fall through the cracks. The answer is to put them on a skewer. So, how do you skewer the jumbo prawns for grilling on the barbeque in the first place?
This may seem like an obvious question that no one dares to ask, but how we'll ask it anyway and answer it too.
The answer is that you skewer them to make them cook as evenly as possible - and to have them be cooked at the same rate as other items on the skewer. This means that for most jumbo prawn grilling you run the skewer through the jumbo prawns so that they can lie flat on the grill and you can grill them on one side, turn them over, and then grill them on the other side. This will give you the most evenly grilled jumbo prawns.
However, if you have vegetables and other items on the same skewer, you may well find that the jumbo prawns grill faster than the vegetables and get over cooked. In this case, you may want to try to skewer them to keep them more compact and slow grilling down more for the jumbo prawns to let the vegetables catch up.