As an employee you are being paid to perform tasks which you will be monitored and judged on. This brings with it new stresses and rewards as you transition into your new role.
Key points to consider:
Maintain a positive, professional demeanour and outlook at all times.
Your interactions with people, both customers/clients and colleagues need to always be respectful and polite, even if you have not been treated in this way.
Maintain a boundary between work life and personal life. When at work leave personal telephone calls, emails and meetings until after work hours and remember not everyone is going to be interested in what you did on the weekend or ate for dinner the night before. Moderate what you say and how you talk about yourself in a personal setting when at work.
If you do need to deal with a personal issue in work time, always provide plenty of notice and reason to your employer.
Think through your tasks and be organised in carrying out your responsibilities, show initiative by considering what else needs to be done which you could do (always seek permission to carry out a new task or aspect of your job first though).
Seek both positive and negative feedback from your manager/employer about the work you are doing and how you could improve.
Don’t be scared to offer ideas or suggestions, but be prepared for - and don't take personally - the possibility that your suggestions may not be taken up.