When I was accepted to Durham I had about 11 months before coming and I was doing some teaching and working (for a publishing company), but I wanted to do something to prepare for my research. So, I started to research heavily in the area of my proposal. Seems reasonable enough…But when I arrived and started chatting with my supervisors, my research started going in another direction and much of what I worked on before was now peripheral. You really can’t be sure that you will end up studying exactly what you want – your supervisors will likely offer you insight in scope and methodology that will put you on a reliable track to doing good research that needs to be done.
So, what would I have done different? First, German, German, German. I know. I don’t love it either, but it really is necessary. Those who say you can get by without it…They were lucky and their examiners were probably in a great mood for the viva!
Second, go back and study the history of interpretation in your wider area. If it is Gospels, go back to the Historical Jesus research and dig in – know the background. You are expected to know it. If it is Paul, read Bultmann and Kasemann. It may be tedious and sometimes dull, but it will save you time, energy and probably embarrassment. I am currently in a class on ‘Paul and His Interpreters’ (with John Barclay) as well as listening to Frank Thielman’s lectures on New Testament Theology on http://www.biblicaltraining.org and it has helped me immensely. It teaches you to see who your own influences are that you might not even be aware of! It teaches you to not try and re-invent the wheel. Your original contribution to scholarship, believe it or not, will probably be a tweaking of something already out there- better you know that now than a week before your viva!
Third, get a feel for methodologies. What will be your methodology for your study? For evangelicals (like me), we prefer good old-fashioned grammatico-historical exegesis, but that is not enough anymore. There are thousands upon thousands of commentaries that offer plenty of that. You need to apply new tools to the reworked ground of NT studies. As for me, I gave to learn ritual theory (ugh), sociology of religion and metaphor theory (a branch of literary theory). I prefer to do grammatical exegesis, but I have to know this other stuff to establish my argument in the scholarly arena and successfully earn a PhD. So, explore methods and see what really interests you. I am fascinated by intertextuality, social-scientific criticism (esp. honor and shame backgrounds), as well as rhetorical criticism. If you can, go and visit various topics at SBL that you might normally ignore and see if anything strikes you as interesting.
I am doing a lot of these kinds of things now and I wish I had more time!