6 ideas
Separate every situation into what is within your power (your judgments, choices, and responses) and what is not (other people's actions, outcomes, your body's fate). Invest emotional energy only in the first category and treat the second as external events to be accepted, which removes most distress at its source.
External events deliver only raw impressions; the harm comes from the judgment you add ('this is bad,' 'I am wronged'). Because the verdict is yours to grant or withhold, you can refuse assent to the distressing interpretation and the event loses its power to disturb you.
Zoom out to picture your life against the scale of all geography, all history, and the vastness of time, watching nations, reputations, and grievances shrink to insignificance. This deliberate change of vantage point deflates the urgency of present anxieties and ambitions by exposing how briefly anything is remembered.
Whatever blocks an intended action can be converted into material for a different virtue — an impediment to one course becomes the occasion to practice patience, justice, or ingenuity. The mind adapts and turns hindrance into fuel, so circumstances can never truly stop a person committed to acting well.
Begin each day by anticipating that you will meet the meddling, ungrateful, and arrogant, and remind yourself these traits stem from their ignorance of good and evil. Because you share a common rational nature with them and cannot be implicated in their wrongdoing, you meet their behavior without surprise or resentment.
Keep constant awareness that you could leave life at any moment, and let that finitude govern what you do, say, and think right now. The point is not morbidity but urgency: knowing time is short strips away trivial concerns and presses you to act with integrity in the present.