Mindfulness is a state of Presence. It is paying attention on purpose without judgement or other disturbing thoughts.
Mindfulness is the quality of fullness of attention, non-distraction. In that sense it is the key to life.
All human beings suffer from a mind full, which is not Mindful at all. If you would record what one's mind produces there would be a lot of noise and rubbish audible. Eventually your quality of life is determined by the quality of your mind.
Mindfulness is an essential part of Buddhism. It is necessary to know the mind, to train the mind and to free the mind from Suffering.
Know yourself by contemplation. What thoughts do you have? What is going on in your body? What emotions do you feel? Don't judge, just observe through Meditation.
Free your mind of any clinging and craving as this limits the mind's Freedom and peace.
Zen Buddha is happy for the opportunity to share this tarot card with you. Show your Generosity towards your friends. Inspire them as well!