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 don't drink instant as my daily coffee, but I do use it for baking and cocktails. When you want coffee flavor in something without the grainy texture of coffee grinds, instant coffee is the best solution because it dissolves entirely. It's great for ice cream, frosting, coffee cake, coffee syrup, or anything else of the sort. I've also found that the quality of instant coffee has improved significantly over the years, so it does actually make a pretty decent cup of coffee in a pinch.
You can add the instant coffee to coffee and some powdered milk to some milk for it and then you'll have more coffee per coffee and milk per milk than anyone else