1. Is my subject knowledge good enough?
I am going to probably upset a few people but the answer is no, your subject knowledge is not good enough. Before you grab your pitchforks let me explain. You may be an expert in your subject and have a degree to prove it, however, teaching a subject is vastly different to being able to do it yourself. To really exaggerate this point, let's take 2 + 2. This would be mathematics most of us would have seen at a very young age and now you can tell me that the answer is four. You have learnt to do this basic arithmetic but to get that stage someone had to teach you what numbers where, what symbols we use for them, the concept of addition, and what symbols we use for operations. Your knowledge will become greater on the course as you won’t just have to be able to do your subject, you will gain the ability to explain every aspect of your subject from the ground up. If you love learning and am guessing you do if you are reading this, this is a lot of fun.
2. Will the kids like me?
When you first enter the classroom some of the students may not like you. They may dislike your subject or just resent you are messing up with their routine and they miss the teacher they had before. But ultimately time heals most wounds and eventually you will have an interest(s) that resonates with pupils and they will at the least get to the point of begrudgingly not giving you much hassle. And yes, you will have classes you prefer and some you don’t look forward to. My biggest piece of advice for this is to set the atmosphere in the classroom. If you enter the room unhappy and deflated, pupils pick up on it and you will seem less approachable. Try and smile or at the very least go in neutral, it goes a long way.
You will, you’re human, and it's great opportunity to show it. What would you do if you forgot someone's name you haven’t seen in a while? You would ask, right? Same applies for students. Like-wise, what if you called Tim, Tom or Chris (yes sometimes you get it that wrong)? You as a teacher are a role model and students likely will have had this awkward social interaction happen their lives as well. Just apologize, again this humanises you and makes you more accessible to students. Do try and learn pupil’s names as it shows you care and is useful for engagement but it is not vital or something you should worry about.
Honestly, this is the most difficult one for a lot of teachers, new and experienced. Schools change policies frequently as everyone is trying to find something that works. Not every technique will transfer from class to class but the best advice I can give is try and be consistent. Fairness is important to students, so if you praise or warn a student for an action, you have to give that same praise or warning to the next student. You will find something that works for you, it may be frustrating at times but ultimately you will be fine and remember they are people too but they are only just starting to learn what appropriate action is and what is not. I’m sure you can think of something that you did at school that you would do very differently now.