Correctly could be hard to pinpoint as even the OEM's have difficulty with this. Some choose soft material and some hard. GM went to a very hard material with very sharp folds back in the 80's. They proved to be extremely durable and still use them.
The boot must articulate in concert with the joint. If a boot rubs on itself it can wear through. It is not rare to find an OEM installed o-ring in one of the folds of a boot in order to realign things.
There can be several items that require a durable boot to be fairly application specific.
I used to work for a Tier 1 CV joint supplier and most of our boots were Hytrel, a Dupont product. I was always amazed that such a stiff boot could work so well. Some of the older designs used neoprene.