>>8903There are a few methods.
The most common is find someplace quiet where you can sit and relax comfortably without falling asleep, you don't necessarily have to do the whole cross leg pinchy finger thing. Simply sitting in a chair can work.
Once you have a place, close your eyes begin focusing on your breath. A thing I like to do is imagine there is a balloon in my head inflating every time I inhale and then it deflating every time I exhale. Breathe slowly and deeply. Your mind is going to wander a lot, but try and remain focused.
The idea is to get your mind to zero in on one thing, and meditating is a good way to practice that and sharpen your focus. Wrestling with your mind to remain focused on something like breathing is basically sort of way to practice your ability to focus.
Start doing it for about 5-10 minutes every day and, if your schedule permits, try to do it for longer. Such practice will gradually increase your ability to focus on one thing at a time.