The entry and exit requirements of Uganda are not so different from any other country. You will definitely need a passport or travel document that is valid beyond one year. Visitors arriving will have to fill in arrival declaration cards that are found at the arrival lounge, the immigration authorities will then give a specific time of stay in Uganda. If a visitor over stays their visitors pass, they will be fined USD30 per day and even prosecuted or deported back to their country.
One must acquire a visa that is now USD50, nationalities that do not have to pay for the visa while entering Uganda include COMESA and EAC countries. Others include Antigua, Barbados, Fiji, Grenada, Lesotho, Sierra Leone, Solomon Islands, The Grenadines, Vanuatu, Cyprus, Bahamas, Belize, Gambia, Jamaica, Malta, Singapore, St. Vincent-Tonga as other exceptions will be specified at arrival.
Health wise, you are advised to have a yellow fever vaccination or certificate to show you had one. Also remember that the entry into and exit from Uganda should only be made through gazetted ports of entry/exit. For the visitors that fall in love with Uganda, you can request for more time to stay from the Immigration Headquarters in Kampala or respective regional offices before expiry of the initial visitor's pass.