calm amongst chaos
A practice that helps me manage the stress in life is learning to find peace amongst chaos. Bringing yourself to center on a sunny mountaintop, after a satisfying meal, barefoot in the grass is easy. Finding that same focus on a few hours of sleep, hangry, soaked from the rain, standing on a crowded subway is another story.
Think of it as resistance training for your consciousness. Getting good at anything comes down to practice: measured breathing, aligning your posture, smiling, and giving yourself time to understand and accept the obstacles you face is a good start. You have little control on the world outside yourself, but you are the only one in control of how you react to it. Stress is an inevitability, and you need to find a way to manage it.
Do what works for you. If all else fails, think about puppies.