To handle a losing session in blackjack, it's crucial to maintain emotional control and stick to basic strategy. Avoid making impulsive decisions based on frustration or trying to chase losses. Set a loss limit before starting to play, and leave the table when it's reached to protect your bankroll. Take breaks if needed to reset your mindset, and always manage your bankroll wisely by betting within your means. Remember, losing streaks are part of the game due to its inherent variance, so it’s important to stay calm, stick to your plan, and know when to walk away.