i read in one of the tutorials on here, that you shouldnt move your eyes even when theyre closed. not even to look at any images you get in your head, just try to relax and let them roll by. sometimes i try to focus on whatever part of the image i can see, but never directly look at it unless its appeared right in the middle.
as for getting excited i guess its something you just have to overcome to really get started with this, as itll ruin your dream if you get to excited in it and all your effort will be for nothing. eventually i just told myself to stop caring, and if i fell asleep then oh well, sleeps healthy either way and theres always another chance.

hope that helps