All Bosnian employees undergo regular health checks to ensure that they are physically capable to do their jobs and that they will not transmit any disease or injure anyone. People in the food industry are particularly checked and random health and safety checks for the premises are held often. Food providers are held to the highest standards. A Bosnian kitchen is expected to be spotless and food safety is very important.
If getting a tattoo then ensure that the instruments are sterilised. While this may be a common practice, one should still be careful.
Since the food is very rich, some extra exercise may help
And as above, never walk off dedicated paths in case of land mines.
Do be aware that the two entities have their own separate postal services, so stamps bought in the Federation cannot be used in the RS and vice versa.
There are three mobile phone networks in Bosnia and Herzegovina: HT ERONET Mostar, GSMBiH Sarajevo and m:tel Republika Srpska, Banja Luka. You can buy a prepaid SIM card from any network at any kiosk for 10 KM or less.
The official languages in the Bosnia and Herzegovina are Bosnian, Serbian and Croatian, all three known as Serbo-Croatian as they are practically the same language. Serbo-Croatian is written in both Latin and in Cyrillic, making it the only Slavic language to officially use both scripts. In the Republika Srpska you'll see signs in Cyrillic, so a Serbian-English dictionary would be helpful there.
Variants among the Serbo-Croatian language differ only in the most academic of venues and also in traditional homes. There are different versions of the language throughout the area and spoken language changes between regions. However, the vocabulary differences are only cosmetic and do not hinder communication between Orthodox Serbs, Catholic Croats and Bosnian Muslims.
A lot of Bosnians, especially the younger generation will speak English. A surprising number of young people will also know at least some German, because many people from Bosnia sought refuge in Germany during the war, or visited relatives in Germany during or after the war. The older generations tended to have studied English, French or German in school.
Many Bosnians speak excellent English, but these are professionals and none of them work in hotels, restaurants, bus stations, or drive taxis. Stated positively, every day Bosnians will insist upon buying you coffee and cakes while engaging you in long and deep intellectual discussions, in perfect English. You'll need to learn a little Bosnian to buy a snack at a bakery and tell a taxi driver where you're staying, but this is easy enough.
Respect the religious differences of the people in the region and their effort to move past the Yugoslav civil war. It is important to be careful in areas where there is still tension and to ensure that one does not offend a particular group due to indifference or sheer ignorance.
Similarly, respect the environment. A lot of the country has been saved from pollution and it is important to be careful of one's influences. Moreover, it is equally important to be careful as the rivers tend to be fierce, the mountains and valleys often unguarded and the footing unsure. Always have a tour guide with you or consult a local for advice on the natural dangers and land mines.