As you begin your journey to learning how to master your mind, you may seek different paths to get there. Masters over the centuries have perfected different techniques and it takes some exploration to find the right path for you. I practice Zazen taught by Buddhist monks but here are a few other options for you to consider.
Transcendental Meditation which was taught by Maharishi Mahesh Yogi. In this form of meditation you are given a mantra based on your persona. This can only be done by a licensed practitioner of TM after which you can learn the technique from the master.
Vipasana where you start by focusing on your breath and then additionally add focus or attention to different parts of your body or your thoughts but always return to your original focus or breathing. The objective is to achieve an understanding that you are separate from your thoughts or your feelings and a distinct entity.
Self enquiry which was taught by Ramana Maharishi where you focus your attention on you the person by asking yourself questions like Who am I? Who is this person feeling this emotion or anger or pain or worry. There is no special position in which you practice this form of meditation and it can even be done sitting though the traditional meditation pose is probably best.
Mantra Meditation where you say the word Om over and over in your mind. It can be coupled with a focus on your breathing and is practiced in the traditional meditation pose.
As with religion there is no single path to achieving mindlessness in meditation. You simply have to find what works best for you.