We always have to start somewhere and at some point. The best time is always now. We can start by beginning to notice and validate our emotional reactions, even if it’s only possible to do so for a fleeting moment at the start.
If you want to grow a lot in mindfulness, and develop competencies that make this a lot easier, I recommend going on a free -0-day Vipassana retreat, and then practicing daily. Go to http://dhamma.org