First thing is to learn to concentrate upon whatever one is doing. It is also good to develop the stamina and hand and feet movement through methodical exercises. Then comes the game. One has to learn the right technique which takes long so a lot of patience is required.
And then play for the joy of it and not with the idea of tournament. Keeping the tournament in mind brings an imbalance and we tend to over-stress at the expense of something else like studies and rest.
So one should enjoy the game rather than play with the idea of success in a tournament. For that one should pray and leave it to the Divine who knows what is best for you.
Affectionately,
Alok Da