Ask questions. Ask questions and then go off in search of the answers. Ask questions, go off in search of the answers and then once you have them, ask MORE questions.
Talk to people you meet. Talk to people around you about what they think about. Talk to people about what they think about and then go find more people to talk to about what they are thinking.
Listen to music. Listen to music that you have never heard before. Listen to music you have listened to over and over again but this time, listen for things you have missed. Listen to music then listen to it with someone else and ask them what they hear.
Watch a tree. Watch a tree throughout the seasons. Watch that same tree over the years.
Experience life as though each experience were designed to enlighten, entertain and educate you. Experience life and then share those experiences in every creative form you can imagine. Experience your creativity and then go find other forms of creativity you had yet to experience.
Always be curious.