One great piece of advice is to avoid only interacting with your co-workers that are around your age. You should branch out and get to know your older co-workers as well. This can be great for you because they have a wealth of knowledge to share with you about how to be successful within the industry, something that can be essential if you are currently working in the field that you want to stay in. They will have insight and tips that you cannot get elsewhere because they have been where you are now. This can also help you to network, something that you know can be important in becoming successful. Speaking of social situations in the workplace, it is important to avoid being part of a clique. This can lead you to gossip or chatting rather than working, which can hurt your reputation in the workplace.
Every workplace has their own culture, so be sure to adapt to it. For instance, if people tend to eat at their desks you may want to follow their lead. Some places are more casual while others are more fast paced. You do not want to be left behind and adapting to this work culture can help you thrive.
You should also know that making mistakes is normal but you should never brush them off casually. Mistakes are meant to be taken seriously (without overreacting) and to be learned from. When you are new to a place, it is expected that you make mistakes as you learn your way around the business. Take responsibility for it and figure out (or ask) how you can fix the problem. By dismissing your mistake as something that is no big deal, you are giving the impression that you do not take your job seriously.
Finally when you are at work, make that your focus. Stay off of your phones. Do not uses social media or texting while you are working, unless you are on your break. If you are going to be successful, you need to have 100% focus on your job. Anything else will be noticed by your employers and this could give them a negative impression of you. Learn as much as you can while you are working. Theory that you learned in school is one thing but being out there and getting the experience can be a more valuable lesson.