One of the best exercises you can do as a photographer is to try to copy the work of masters. Even though you obviously will not use a copied photograph in your portfolio, the techniques you learn will be invaluable to your own work.
Coming to you from The Art of Photography, this great video discusses what you can learn by trying to copy the work of master photographers. This might seem like a waste of time since you can't use the images in your own portfolio. However, it teaches you to read light much more precisely, and in the process, it helps you gain deeper insight into the technical and creative processes behind the photos. Of course, these lighting skills will help in your own work, and the creative insights you gain can be applied to your photos, but perhaps the greatest benefit comes from the process of reading the original image. In doing this and making the connection to the lighting setup and other factors, you will gain a greater ability to translate ideas in your mind into actual photographs. This in turn will better enable you to explore your creativity. Check out the video above for more.
thats how they learn in painting.they first draw basic stuff , and then learn by copying master piece.it give practice for gesture and learn your eyes to see things.same in photography, you need to train your eyes