Your first step in assembling a great demonstration is to develop a list of all the features you can find about the product you will be presenting. Secondly develop a corresponding list of the benefits of each feature. We call this the F/B list. If you can customize the benefits directly to your prospect even better. For example, you might say, “As an Audi technician this tool will help you secure those hard-to-reach bolts behind the starter.”
Now put those F/Bs in a logical order. Back in my KNIPEX days we would start at the tip of the jaw and work our way back through the blades then to the joint and then to the end of the handle. A feature is the cross-hatch jaws, and a benefit is that it gives you great gripping power without slipping, etc.
The reason to put these in a logical order is so you can easily remember them. If the product has an on/off switch, start there. Jumping around as you present the features may cause you to miss an import feature and could also confuse the customer.
I know that after you have demonstrated a tool 50 times you start to get a bit bored with it. Think of it this way: You go to see your favorite musician and they cut out verses because they are bored singing the song. You go to a play performance, and they skip act two because they're tired. That will never happen nor should it with your demonstration. That feature/benefit you just skipped could very well be the difference between a sale or no-sale.