Since I'm thinking in numbers, something that keeps popping up in my head lately is that I feel like my research is maybe 80-90% "good," if that makes sense. The missing 10-20% is due to mistakes on my part-- including lack of preparation, forgetfulness, oversights, etc.-- and uncontrollable factors-- barriers to fieldwork, data, etc. I think part of writing my dissertation will be carefully screening for these errors and missteps and taking them into account.
I've been deeply engaged in my fieldwork for about a solid month now, and if I could go back in time and warn myself/congratulate myself, here's what I would say:
-Narrow your research question down. Cannot stress this enough.
-Have a good local institutional contact. Meet them before deciding for sure. You may be desperate, but don't settle for things like people not responding to your emails in a timely fashion. (In my case, things have worked out very well with my host institution.)
-Prepare as much as possible before going to your fieldsite. Test your interview questions, have them translated, know what sources you're looking for. Anticipate what types of analysis you will do and how your methods will answer your questions and be amenable to analysis.
-Understand some of the local cultural context, especially with regards to interpersonal communication.
-Have a very specific set of requirements for what you want to accomplish during your fieldwork; one that you can communicate with others. In my case, this means clarifying: what type of scientists I want to talk to; what exact books/reports I'm looking for; how many farmers I want to talk to; etc. People cannot psychic-ly know what you need. Be open to suggestions and negotiations with your local hosts, but firm about why you want to do certain things.
-Related, don't be afraid to ask for things. Things which I've had to ask for, which seem stupid to me but otherwise I would have no other way of getting, and eventually I have mostly gotten over the awkwardness: bottled water, please make the food less spicy, please no more aloo parathas for breakfast, hygiene products, money, etc. Relevant article about asking for things and being an introvert.
-Make a budget. Try your darndest to get someone else to pay for it.
-Take notes, edit notes, back-up notes, read notes often.
-Network. Don't be afraid to talk to people. Talk to the big-wigs. Talk to the maid.
-Be patient! Be flexible. Take what you perceive as set-backs in stride. Have faith in people who are helping you. Do not lose your calm.
I'm sure I have many more lessons left to learn! Also if anyone reading this has any agricultural research/India specific questions about fieldwork preparation, I have a whole host of answers. Rule number one being: bring your own toilet paper, a hat, and bug spray.