Before you travel abroad, we would advise you to consult your General Physician regarding the vaccinations that you must get. It's better to visit the clinic at least 2 months before traveling since some vaccinations need a couple of shots. Sometimes, you might also have to provide the Proof of Vaccinations while applying for the Visa.
If you are going to any of the North American countries, you may not need to get vaccinated, but most countries in Africa, Asia, Latin & South America require some sort of vaccination. Some common vaccinations that are required for traveling to most of the countries include Hepatitis A and B, Tetanus, Typhoid, and Malaria. In case of visiting most of the African countries, getting the Yellow Fever Vaccine is a must.
For more information, you can take a look at the official website of Centers for Disease Control and Prevention, where everything about the travel vaccination requirements are mentioned in details. Also, consult with your doctor regarding any other medications that you might require, and also carry your regular medicines.