As a beginning meditator, knowing where to start can be challenging. Simplicity is key.
According to this post from Suite101 the quickest way to ground is through the breath (and the quicker you ground the quicker changes can occur). By focusing on the inhalation and the exhalation, a person moves awareness away from the busy brain to the simplicity of the breath. This type of grounding meditation lays the foundation for other meditations.
A good follow up to a grounding meditation is an energy meditation which gets you in touch with your life force and potentially any blocks which are negatively effecting your well being.
A grounding meditation not only can bring focus to your mind and life, it can also be a stepping stone for a wonderful energy meditation. An energy meditation can give you the opportunity to feel relaxation no matter what type of the day you have had. It is good for the health, both mentally and physically. All you need is a quiet place to meditate and some good breathing techniques to help you learn how to meditate.
Read more about meditation exercises for beginners including a guided meditation inspired by Stephan Bodian, author of Meditation for Dummies here.