The world is your tripod. Try to compose every shot like a still. Fill the frame. Make sure you have an opening and closing shot. Anticipate genuine moments and have your shot composed and ready to capture them.
Faces tell stories.
Get your camera close. Don't shoot close-ups from across the room. Put your microphone where the sound is. Ask questions that require a sentence to answer. Ask questions to evoke feelings, emotions, and opinions, not facts.