This piece has some good core information from a non-business focused blog, lifehacker.com.
Things I liked of note (that apply to the life of a career, not just your first job):
Be on time, stay organized and never miss a deadline
Of course exceptions exist for legitimate reasons but as a general rule, it’s a good guideline. One unspoken reason is that you may have been delegated some “small potatoes” stuff for your your earliest tasks that are essentially tests to see if you can handle bigger stuff. If these can’t be delivered on time, it’ll raise alarm bells. I’d also add that I have seen many new hires struggle with assignments that have no deadlines and these can be more deadly than missing deadlines for people who don’t tend to be closure driven. Best advice is that you try to negotiate a deadline for things for which no hard end date exists so that expectations are clear with everyone.
Pay attention to company culture
This is can be hugely important and yet really difficult to discern. Though you are always free to go against the grain of any company norms, you may want to be aware that you are doing so given the negative implications that may ensue. If you suspect that it will be difficult to pick up on norms, you can always ask – e.g., Are those staff meetings considered mandatory?
I agree with this, though with a bit more caution than these authors propose. As a manager, I am a fan of questions to some extent but much less so when the answer is discernible with minimal effort by the employee themselves. By all means however, ensure that you clarify instructions to save time later and in the early days, ask more questions to understand the context of the particular culture in which you are working.