In hindsight, my cautiousness in choosing a Ph.D. project, place, and supervisor was well rewarded. I have been happy with my project, the project-specific support I have received, and the stimulating research environment I have experienced. I first ventured into the field of developmental genetics as a Master's degree student. With this initiation, the fruit fly Drosophila melanogaster appeared as the model system of choice for studying developmental mechanisms. Because Cambridge has an extensive community of researchers working on the fruit fly, I looked for a Ph.D. place there, and I have spent the past three and a half years studying aspects of the control of unique segmental morphologies along the long body axis.
However, in my time as a Ph.D. student I neglected to acquire the skill of shaping a balanced working day, with hours for work and hours for play. My failure to work out a balanced schedule in the beginning was a serious omission, and I bet that some of the hard times I went through could have been avoided.
During a Ph.D. it's important to have as many sources of support as possible available to you. You want to be at an institution that provides settings for social encounters, easing away the difficulties of talking to new people. You want to be among international students, providing insight into different cultures, political systems, and opportunities in the world's job market, and offering the chance to widen your language and communication skills in an international setting. Knowing many different people will allow you to observe, or even participate in, people's career decisions. This is far more valuable than a formal encounter with a careers officer, so consider the social environment when choosing a Ph.D. place.
At the beginning of your Ph.D. you can be sure to find yourself in conflict with your supervisor--you want to adapt to a new place and your supervisor wants you to get started on your project. Getting started is important to you as well, so you might just yield to the pressure to invest a lot of effort straight away. Don't! First meet people, find out about the town and sources of invigoration. You will need them.
Also remember that everybody who starts out will encounter this dilemma, so take advantage of the institutional beginners' or freshers' week to socialise and find out about the opportunities of the place. Do not think you can do it later--the opportunity is not going to come around again for another year! There is only a short window of time when people starting a busy Ph.D. are seriously open for new people. Be present in that time, it will give you a chance to choose your social environment. And in 12 months time, be sure to meet next year's intake of people. Your fellow students are your most important resource.
Try new things, even if they sound alien to start with. Let yourself be enticed by activities your fellow students suggest--something might just suit you perfectly and you would never know if you did not try. Don't just stick with what you always liked to do--much too easy given the Ph.D. pressure. Universities are environments where you can design your very own education programme around your Ph.D.--don't let that opportunity slip by. Master the art of not becoming a victim of your Ph.D. Work will tire you out if you do not balance it with activities richer in experience. Thinking about your work does not leave memories in the same way as experiences that are accompanied by emotions.
Try not to live in a student ghetto. Whenever I lived in normal neighbourhoods with old people, young families, and young professionals I fared best. Too much exposure to grumpy and bitter Ph.D. students is not good for you! Do not underestimate the amount of bitterness undertaking a Ph.D. can foster in people!
Go away from your Ph.D. town on a regular basis. Things are bound to come into perspective! As going to Europe is very affordable these days, take advantage of your loose schedule. Realise that your current straightjacket is just a very special circumstance and that there are lots of alternative scenarios for living your life!
Having been in full-time education before starting a Ph.D., I found the degree of professionalism expected from me a little hard to accept. I thought I was in for another educational experience rather than working in a job centred on a project. Part of my wrong expectation was that my interest to get to know my supervisor well would be reciprocated. Under no circumstances expect that your supervisor has the time to acknowledge you as a person in a meaningful sense. You can expect to be guided through your project--not your life!
How can you make the most of your supervisor and your colleagues with respect to your progress as a scientific thinker? Be aware that everybody in science suffers from a chronic shortage of time. Only if you can offer interesting conversation will you be able to obtain feedback on your ideas and your project--especially the conceptional side of your project (everybody can tell you at no expense where the copying machine is). The art of fishing for feedback includes identifying the right people to talk to. Literature searches identify previous, and research seminars current, interests of people. Only start bothering someone after sufficient thinking time by yourself. Ideally write down your ideas in an easily digestible format and offer this text to the person you want to consult. It sounds formal but will give you a very good starting point for discussion.