dissolve in cold water, ONLY THEN add hot water. The rationale behind it is that aromatics evaporate too quickly when the instant powder is infused with too/boiling hot water.
I was recently on holiday where most of the other guests in our hotel were 50-70 year old Germans.
The breakfast buffet at our hotel had a large scale coffee maker which could do some surprisingly good freshly ground coffee. What it could also do is spit instant coffee into your mug and pour hot water on top.
In two weeks I never saw someone (other than me) draw anything but fucking instant coffee from that thing.