I’m in the middle of the same thing, @emilyrose.
As @Darwin said, make a list of the projects you worked on the past year and specifically, your contributions and accomplishments.
Also, compile a list of any training you took, either formal or self-study or whatever. And be ready to explain any training you’d like to take in the near future.
Be prepared to enumerate the things you like about your job and those things you’d like to see different. Focus on positive contributions you can make… not how others can change to better suit you.
And then, be ready to answer questions about your career goals in the next 6 months, 1 year, 2 years, beyond. You needn’t be real specific. But you need some kind of answer at the ready. It’s your career and you should be prepared to speak confidently to it. Short term, I suggest “focus on improving delivery” of your current tasks and longer term, I suggest some role with increased responsibility. And you should have some cursory ideas on how your current work and upcoming training and manager’s help can help you accomplish those goals.
Dress nice. Clean and organize your desk (if s/he’s coming there.) Make eye contact. Don’t fidget. Be yourself.
And remember: you’re good at what you do. You can take on more and be great at that, too.