Repeat exercise one, but this time, add sound to the scene you are constructing. That is, you should be both visualizing pictures of the scene being constructed, as well as imagining in an auditory sense the scene being constructed. Spend at least 10 minutes a day doing this, but not more than 20. Count all of your breaks in concentration, and put your records in your journal.
Do not proceed to the next exercise until you can count three or less breaks in focus during your time constructing a scene. Thinking about constructing a scene is to be considered a break in focus.
It is acceptable and actually advisable to switch up the scene you construct. This allows you to remain interested in practicing.