#1 - Having Too High Expectations
When you're graduating from college you think that your future job is a dream job. That it would be as perfect as you always imagined. Well, we all think that way until we face the reality. The thing is every job has its pros and cons, and there will be a lot of hard work and a lot to learn before it starts being at least on half that romantic as you thought it would be. But, a lot of people face such kind of disappointment at the beginning, especially those who weren't realistic from the start. What you need to realize is that any job is not a piece of cake. Every position in every field has its dark sides and difficulties. But if it would be that easy it wouldn't be fun.
#2 - Bombing An Interview
In the beginning of a career we feel like we can take over the world. We feel over-confident and allow ourselves not to prepare for an interview properly. And then this happens. You're going through the interview and think you did pretty well, but then you start googling the questions interviewer asked you and realize that everything you said and done was wrong. That is definitely not the kind of situation you'd like to repeat. If this happened to you - we're sorry. But if you haven't been there yet - here's a lesson for you: always do your homework.
#3 - Feeling Shy To Talk About Money
Well, that is a mistake that everyone does in their 20s. You're a rookie, don't have a lot of experience and sometimes, simply don't know what you are worth. So, beforehand find out how much professionals of your level earn and seriously think about how much money you'd want to earn on that position. Try not to hesitate, it's better to discuss your salary when hired that have an unpleasant surprise later.
#4 - Trying To Please Everyone
Inexperienced workers often commit one simple mistake - they take initiative to show how productive and smart they are and then realize that it's much more then they could handle. It's okay not to know something, especially at the very beginning of your career. But biting more than you can chew just to become your bosses favorite or to make colleagues respect you is not the best way to succeed. If you want to earn good reputation make sure you can make job done good and in time before taking initiative.
#5 - Ruining Relationships With Your Boss
Unfortunately, there's a high chance that your boss will be a toxic person. Or, maybe, a co-worker that you, simply, hate for some reason. The worst mistake you can do is letting them impact on you, your job and your career. The best thing you can do - is to take control over your emotions and reactions, be a professional and try your best to coexist peacefully. It will be hard sometimes, but eventually you'll have a priceless experience of dealing with toxic people, and those you will meet in your life a lot.
#6 - Being Scared To Make A Mistake
When you're a newbie and everyone else at the company is not you might feel really insecure. And sometimes this insecurity flows out into a fear of taking the smallest decision without the directions from your manager. But it's not a preschool and no one has the time to hold your hand. You shouldn't be afraid to take initiative just to avoid making a mistake. No one promotes passive and unconfident people.
#7 - Messing Up And Covering It
We all are humans, and we tend to make mistakes sometimes. And when it's your first time it can be intimidating. But trying to cover it up is not the best idea. If someone finds out about it you'll have much explaining to do, boss will see you as a liar and you risk even to get fired. If you really messed up - the best decision is to come clean, admit your mistake without making any excuses. It will show that you are a mature person who takes responsibility of his/hers decisions. Tell your boss that you've learned your lesson and ask what can you do to make it right.