Like someone above said - ask questions! And show initiative. Don't stand around waiting to get "invited" by the nurse, respiratory therapist, etc. to observe a procedure . No harm in asking "Is it okay if I come observe?". The worst they can say is no! But by asking I learned a lot and had anesthesiologists walking me through the epidural process and open heart surgery, respiratory therapists teaching me about tracheostomies, nurses showing me some crazy wounds and how to debride them, etc... We had several people in clinical who always complained that they "never got to see anything". Just ask politely and without being obnoxious!
Good luck with clinicals!