Say "buenos días" for good morning, "buenas tardes" for good afternoon, and "buenas noches" for good night. Theses are the 3 most commonly used greetings in Spanish. Be careful to use buenos with días and buenas with tardes and noches.
Learn "Hola. ¿Cómo estás?" to express "Hello. How are you?" You can also use "¿Qué tal?" which means "What's up?" These Spanish phrases initiate a conversation with another person.
End the conversation by saying, "Lo siento, pero me tengo que ir." This means, "I am sorry, but I have to go." You can also say "adiós" which means "good-bye" or "chao" which also means "good-bye."
State "nos vemos" or "hasta la vista" which both mean, "See you later."