The Dream Machine allows you to enter the dreams of the 4 villains to recover the 4 "totems." You will need items from one dream to use in another dream. Press the selection buttons (up or down) at left, then the button on the right to enter the dream. Except when you complete a totem, you have to press "wake up" (or the dream exit) in order to leave a dream.
You will have to go back and forth to the 4 dreams to get the items you need to obtain each totem.
- The paint cleaner for dream 3 is in dream 2, and the sprayer in dream 4.
- The crystal key for dream 1 is in dream 3.
- The shrinking potion for dream 2 is in dream 3.
- The drill for dream 4 (part 2) is in dream 1.
So the most efficient path is dreams 2, 4, 3, 2, 1, and 4. You get the turpentine in 2, the sprayer in 4, the shrinking potion and crystal key in 3, and the diamond drill in 1.
* For the complete solution, see one of the related questions below.