Health Get your injections, Hepatitis A, B, Japanese Encephalitis, Meningitis, Polio, Tetanus and Typhoid (now in pill form), before you leave. Take anti-malaria medicine faithfully. I used Lariam (once a week) had no major side effects, I was just a bit uncoordinated the day I took it. These precautions might seem expensive but they're worthwhile.
Have a check up when you get home. I tried to be careful but picked up an intestinal parasite. I didn't have the usual symptoms; (diarrhea etc.) just felt a bit down and lost my appetite. I didn't know those are symptoms of a parasite. If they stay in your system they can affect your liver and cause long term damage.
Have health insurance for travellers or some extra money in case something happens. In Chapora, near Vagator there is a Library Ashram run by Scandinavian volunteers. They not only have a lending library, they serve free meals and they are in contact with local doctors, hospitals, lawyers, embassies etc.