Usually saying the chant and photofocusing keeps you in the state. Focusing on the back of the head while photoreading can be fun and it triggers the brain into action. Keep using photoreading, in time keeping the state and seeing the 4 corners will be easy.

Feeling sleepy while photoreading, yes you probably were photoreading. Your mind was relaxed, maybe even a little too relaxed. Just keep photoreading, try different times of day with practice you will find the right level of relaxed alertness for you.
Good for you, that you are noticing your dreams more since that means you are developing the inner mind conscious mind connections.
For the article on Memory Loss during Exams you're welcome 
Alex