For each of the components, have a plan B, even plan C: Be flexible about pretty much everything. For example, if you rely on making copies of questionnaires, would you still be able to collect data if the copier in the field office fails? Etc. It's always good to mentally play a couple what-can-go-wrong scenarios when planning the study. Do so within reason, however, or you may risk stressing out yourself.
Incorporate some immersive observation of the field: If safety and cultural environment allow, try to observe more as a bystander. For instance, a patient with diabetes may tell you that she always wears shoes to protect her feet when walking on the dirt, but in fact the local people may only own one pair of shoes and they only wear them in festivals or when meeting with visitors.
Learn the local languages: Interpreters in some places are not exactly fluent in English, knowing some of the local languages can help you better engage with the process like interview or daily dialogue. It will also facilitate your mixing-in with the community.
While you're there for your research, also think how you can benefit the community: For instance, you may volunteer some time to work, train some locals to empower them, share with them your results at the end, liaise local stakeholders to address your questions and give input to your solutions, etc. If possible, be more "by the community, for the community."
Back up and back up again: If you use field note, get the ones with the brightest cover so that it's easily recognized and less likely to be lost. Written and drawn field notes should be photographed and archived regularly. Computer records should be backed up into at least two other media (external hard-drive and/or encrypted cloud storage.) Don't store your external hard drive and work computer at the same place (e.g. left in the car or office together.) For people who might have picked up your lost notes and wanted to return, make sure your equipment and notes have a contact method (like the address and phone of your host organization) to reach you. If possible, do not leave your personal address if you'd be living alone.
Backward engineer from your products: A day-by-day routine may be difficult, it's easier to set up milestones along the way. I found it useful to decide what the product will be (say, a 1,500 word literature review x 5 parts) and then give them an estimated duration to complete, followed by fitting them into the calendar. Once the big skeleton is in, then do the finer level like weeks/days to determine daily word quota you'll need to fulfill. Give everything some cushion time. Most of the time, I found myself underestimate i) transportation mishaps, ii) local festivals and holidays, and iii) administrative difference, like some clinic can just close for the day because they gave out all their medicine in the first hour after opening.
And I totally agree with another answer that you should start entering and evaluating the data as soon as they are ready. Time to time I've found questions being misunderstood. E.g. I had respondents answering an English-to-Portuguese question "What is your top three favorite foods?" with "Breakfast, lunch, and dinner." Knowing something has been lost in translation allowed us to correct the question quickly.