To avoid giving away tells, maintain consistent behavior regardless of your hand strength. Keep your posture and movements steady, avoiding sudden changes when you get a good or bad hand. Control your breathing, keeping it slow and even to avoid revealing nerves or excitement. Handle chips and cards the same way every time, using deliberate and consistent actions to minimize clues. Avoid excessive eye contact or nervous glances, and try not to speak or change your tone when in a tense situation. Cultivating a neutral and calm demeanor can help mask your true intentions, making it harder for opponents to read you.