Just some small things I am considering these days:

1. Work with your advisors: not be driven by them, but learn and discuss with them.
2. Being a graduate student is about learning what is scientific research, practising how to do research on your own, not by your supervisor.
3. Be active and communicative, then you can grasp the chances.
4. There is no need to compare yourself with others (you are a unique individual, how can you quantify the difference with another person?!). Thus, doing your own best is the goal. Challenge yourself!