Some ideas....
You could find an attending who is a good teacher and stick with his/her rooms. Avoid rooms where the attending is not a good teacher or doesn't care (this is not a good use of your time if you need a letter of recommendation). Remain in the room when the attending comes to give breaks -- this is a good time to ask questions and show that you've been reading.
Show respect to the CRNA's. Get out of the "just a CRNA" mentality and remember you're in their room, it's their case, it's their territory and you have a lot to learn from them. If you are respectful rather than demanding, you will get a lot more out of those cases. And, avoid the rooms of any CRNA or resident who doesn't like to share and let you participate in the case.
If going to a resident-run case, pick 2nd and 3rd year residents. They are more able to share their cases than 1st year residents at this time of year.
Bring a book (anesthesia book) to read. Don't be afraid to just grab a stool, sit down and read during the case to keep yourself busy.
Be cautious about asking (anyone) for the intubation too early. This can be awkward -- oftentimes people like to get to know you before offering you any procedure of their own accord. Make yourself available and let them tell you what they want you to do -- if they want you to bag-valve-mask, just do that (it's equally hard and the more basic skill to learn).
Anesthesia for students really is a lot of shadowing. The best way to get a lot out of the rotation is to read around each case, ask lots of pertinent questions (that's how you do well in the rotation also), and once you establish a relationship with whomever you're watching and demonstrated that you are curious, participation in the case will come your way.
