It's been a while since I have had a student teacher, but I expected the following (not necessarily in order of importance - just off the top of my head.)
Follow thru with the management plan I have set up. Some minor tweaks are OK, but things will run more smoothly if things aren't changed midstream. However, I always loved to hear new ideas.
Don't be afraid to be creative, but don't think you have to have something creative for every lesson.
Don't try to be the students' friend, but be friendly
Come prepared. Winging it is necessary sometimes in this profession, but it seldom works unless you have experience.
Ask for help, advise, confirmation, etc. when you need it. Don't be afraid to. Remember, your CT is your instructor during this time
If you notice something about a child that seems unusual, talk to your CT about it
Understand that teaching requires more hours than the set school hours and sometimes it means working over the holidays.
Of course student teaching for special ed is not the same as a regular classroom, so hopefully some SPED teachers will see this and respond.
Best of luck to you!