You should at all times be on the alert for a chance to put the enemy under the necessity of doing two things at once - and you should try to avoid putting yourself into such a difficult situation. This means that the key to success in chess is A DOUBLE THREAT. A threat to one enemy piece alone is normally parried with ease and is worthless except for some reason ulterior motive. But a double threat is terrific.
You can play chess with the wizards of the chess world, living or dead, anytime and anywhere you like. The wizards' games are printed and you just play the games over, understanding a little at first but gradually more and more. You can imagine how a player would improve if he had a champion always at his shoulder to show him what that champion would play instead of the move the player himself had thought out.
At each move you should spend a little time thinking out a move yourself, then uncover the text move and compare it to yours. Looking first is useless.