For those considering entering a doctoral program or those currently in one:
Be realistic: Know what resources are available to support a 3-5 year commitment, which may include field research. Graduate teaching positions tend to be available, but won't cover all your costs alone. Be aware of your financial needs and potential resources.
Time Management: Particularly for graduate students that haven't spent a lot of time outside of academia, time management is crucial. Have "working hours", "work days" and writing objectives. Set timelines and have goals. Your supervisor is there to help you, but is not there to hold your hand throughout the process; the one person that is going to push you towards completion is you.
Supervisors & Committee Members: You want to have academic supporters that are not only familiar with the field of your research, but also ones that are conversant in the area of you specific research. Otherwise you might often be alone in dealing with the socio-cultural, geographic, historic and political specifics. For some, this may not be a major concern, and general specialists as supervisors and committee members will be sufficient. If you feel you need that support, make sure to consider it as you may be the only one in your department with that specific focus, and at times that can be challenging.
Balance: Know where you can invest time that will help build your knowledge, skills and CV, and recognize where investing time will detract from your progress (or be a form of procrastination). Joining every committee and group that crosses your inbox will put you behind in your own research. That is not to suggest that such opportunities are not worthwhile, but they also ought to not be overwhelming. Moderation is everything. Also, consider taking positions that will build your experiences and knowledge, particularly ones that you don't have experience with, rather than repeating things you've already done.
Referencing: If you are applying for funding or writing proposals, consider the readers/reviewers. You might feel your work speaks to the literature, but make sure the readers also feel it speaks to the literature. This is particularly the case if your research speaks to a subject or place that reviewers may not be as familiar with as yourself. In most cases this means stepping back and exploring some of the theoretical and methodological literature related to your proposal.
You are not alone: There are more doctorate graduates than there are professor job openings. Some estimates (depends on the data, country and department) suggest only 10-20% of doctoral graduates end up with tenured positions as professors. Not everyone is trying to get those jobs, however you should be aware that the market is not short of potential candidates. Long story short: you need to stand out from the crowd because there is no guaranteed professor job waiting for you. In order to so this, you need a strong academic profile, including conference presentations and published works.
Conferences: Graduate students are told to build their resume with conference presentations, this is true, but also recognize that many conferences are more about building your ability to prepare for and give good presentations than they are actually presenting your findings to the world (in other words, it is common to have 5-20 people listening to your presentation, most of whom are attending because they too are presenters at the conference). Second, conferences are a great place to network, which is one of the most important things you should be doing in preparing to be on the job market (see below). Last, but certainly not least, you don't want a CV full of conference presentations that lacks publications. Try to have your presentations lead into publications.
Publish or perish: In many universities this is very real. Hiring committees look for publications, and may assign points based upon them. In this competitive environment, for the social sciences, that often means an unstated expectation of 2-3 articles a year and a book every few years (varies with university and department). Some universities are not as strict with regard to publishing expectations / requirements, however it appears to be the norm and also appears that this will continue to be the case as there are more potential applicants for positions. Importantly, where you publish matters. Although you might support the idea of open access because it makes your research more available, some of the journals you publish in need to be ISI-ranked, peer-reviewed and ideally top in your field. Does that mean that your work will be more read? No. Recent research suggests a significant shift is taking place whereby non-elite journals are cited far more often than was common in the past – however universities have not shifted as quickly. If you do opt for publishing in journals that are not ranked you can demonstrate the impact of your research by the number of people that cite it (with Google Scholar) or number of people that viewed it (somewhat harder, but Academia provides one platform for this). Peer reviewed and ranked journals do tend (there are exceptions) to have higher expectations and more rigorous processes, you'll find the feedback from such journals may reflect this. There is no correct answer on publishing, but knowing the context helps you make informed decisions.
Networking: Academia is like most other sectors, who you know is sometimes just as important as what you know. This is particularly the case for research work outside of the university setting. Mingling at conferences can lead to consulting work, research projects and potential jobs. Even networking on campus with professors aligned with your research interests may result in research positions. Many times such jobs, particularly those on campus, are not widely advertised and are given by professors on a case-by-case basis. It is unlikely that these positions and professors will come find you, so you will need to find them.
Playing the game: Sometimes, whether we like it or not, we need to recognize that there are (unwritten) rules to the game of academia. If you want to be successful, you need to understand and work with the rules of it. Deciding where and when compromise is an individual choice, making informed decisions is what is important.