My friend without any decent training of photography is able to take a nice colour and composition photograph. Somehow I believe that artistic talent is in-built in us and we just need training to bring that talent to the max.

Sketching is the fundamental process of creating anything: games, movies, products or even a painting. Sketching is the idea creation. It is about scribbling down notes or fast sketching of some interesting things you come across or even appear in your dream. Master the technique of sketching and you will have a strong foundation of creating anything. Drawing is only important to fine artists, but even before they start to draw or paint their canvas, they will also sketch their idea and composition too. Have you seen Michelangelo's and Leonardo da Vinci's famous sketches?
Sketch everyday if you can. Is a good exercise for your eyes, hands and brains.
"I should recommend . . . keeping . . . a smallmemorandum-book in the breast-pocket, with itswell-cut sheathed pencil, ready for notes on passing opportunities: but never being without this."John Ruskin, The Elements of Drawing, 1857