I used to make 1 off, custom footbeds (orthodics) for people actively playing sports. Primarily ski boots (as it was a ski shop)
We used higher density foam than Hydroturf and had to shape it around heel cups, create forward lean, etc.
We heated the foam up in a convection oven on low until it was mushy. Adhesed no problem.
The nose piece would be too big for a toaster oven, but you could do it in a regular oven.
A heat gun will also outlast a hair dryer, its better to use one, just take your time and keep it on low.
I'm using my kitchen oven for my ski though. You'll see...