Walk back into the room keeping the thoughts you want to have
or (less effective) vividly imagine doing so.
Think with your eyes closed more often
or close your eyes when you notice your thoughts becoming important. (Not while operating heavy machinery ;)
Meditate deeply on the connection between your thoughts and vision, and potentially learn to notice thoughts slipping soon enough to consciously intervene when it happens.
Walk back into the room keeping the thoughts you want to have
or (less effective) vividly imagine doing so.
Think with your eyes closed more often
or close your eyes when you notice your thoughts becoming important. (Not while operating heavy machinery ;)
Meditate deeply on the connection between your thoughts and vision, and potentially learn to notice thoughts slipping soon enough to consciously intervene when it happens.