Tip 1: Don't be late! If you're late, you're fired. Unless you're a doctor. Then you're just a late doctor.
Tip 2: Don't wear your pajamas to work. Unless it's Casual Fridays. Or you're a startup. Or you're a startup in a startup.
Tip 3: Learn to use the copier. It's not that hard. Even a trainee can do it. But don't try to staple the copier, that's just asking for trouble.
Want more Trainee Tips? Check out our subpage on Advanced Trainee Tips for more advice on not getting fired!