Before creating a game, set the difficulty to one level above the level you normally play the game at (for example, if you want to play at Torment 1, select Torment 2). Once the game begins, pause the game, and lower the difficulty level by one. Then, when you are about to turn in a quest or complete a bounty, pause the game, and select the highest difficulty available (should be two levels above the difficulty you are playing at) to get the rewards of a higher difficulty without having to defeat stronger enemies.