They often find themselves going over texts for the first time just a few days before the students do. Unfortunately, there is no simple remedy for this situation. During your first year, you may simply have to do a lot of last-minute preparation. It will be easier, however, if you talk extensively with your colleagues in the course. Help them in your strong areas while they work with you on theirs.
Experienced hands can be of particular assistance.
You'll also be more effective if you realize you can and should tell students when you don't know something. It's important for them to recognize that scholars continue to learn all the time. If possible, tell them how you'd go about finding an answer or bring it into the next class. Usually student attendance, degree of participation or responsiveness, and even expression, gestures, or body language will give you some indication. Yet, you still won't know what needs improvement or how to improve it if you don't do some sort of more telling evaluation.