Stoicism is the ability to quickly differentiate what you can control from what you cannot. Once you are able to practice this ancient art successfully, your existence will look and feel very different. One book I have been enjoying on the topic is 'The Daily Stoic by Ryan Holiday'. Check it out for daily shots of stoic wisdom.
What you need to know:
1. Events don't upset us, beliefs do.
2. Control what you can. Ignore the rest. To quote Baz Luhrmann 'Don't worry about the future or worry that know that worrying Is as affective as trying to solve an algebra equation by chewing bubble gum. The real troubles in your life are things that never crossed your worried mind. The kind that blindsides you at 4 p.m. on some idle Tuesday'
3. Accept everything without being passive. (read The Surrender Experiment by Michael Singer)
4. Morning and evening rituals are fundamental. You have to set yourself up for the day (or prime yourself as Tony Robbins says) as well as reflect at the end of it.