A very effective way to control and direct your thoughts is with other thoughts. For example, in your mind you can construct a “thought shield” which you can use to literally cause negative, wasteful and destructive thoughts to bounce right off of you. Once you have something positive upon which to focus your thoughts, it’s easy to build that mental shield and program it to simply deflect all the wayward thoughts which might otherwise cause you to lose your focus.
Visualize in your mind a physical shield around your body, made of a hard, yet somewhat “bouncy” material such as the neoprene that’s used for wheels on roller skates. When you sense a negative or unwanted thought approaching, imagine that thought simply bouncing off your shield and dropping harmlessly to the ground, where it loses all its momentum and then fades completely away.
Whenever that happens, use it as a cue to re-focus your thoughts on whatever it is you have decided to accomplish. So not only will the negative thoughts bounce off of you, you can use the opportunity to give more energy to your focused, positive thoughts.