Stress is one of the most common problems of modern life. Stress is an emotional and chemical response to stimuli around us, but the problem lies inside our heads. Stress is most often associated with lack of time or money, or by relationships at work, home, or with family. Achieving better emotional control helps some folks handle stress much better than others, but some situations are inherently more stressful than others.
Ideally, the long-term solution to stress is to overhaul your attitude via personal development work. But while you're working on that, there are some strategies to help you cope in the short-term.
If your stress originates from too little money, the logical answer is to get a better-paying job. Too little time: slow down, prioritize, be realistic, and focus. Multi-tasking is a crazy-making oxymoron. If your stress originates in your relationships, stop blaming other people; stop trying to control other people; and focus on your own life and its direction.
The best solution over-all for dealing with stress in the short-term is to know your values and your life's purpose and to stay grounded in yourself.