Concentration is a cornerstone of mindfulness practice. Your mindfulness will only be as robust as the capacity of your mind to be calm and stable. Without calmness, the mirror of mindfulness will have an agitated and choppy surface and will not be able to reflect things with any accuracy.
Jon Kabat-ZinnGenerosity is another quality which, like patience, letting go, non-judging, and trust, provides a solid foundation for mindfulness practice. You might experiment with using the cultivation of generosity as a vehicle for deep self-observation and inquiry as well as an exercise in giving. A good place to start is with yourself. See if you can give yourself gifts that may be true blessings, such as self-acceptance, or some time each day with no purpose. Practice feeling deserving enough to accept these gifts without obligation-to simply receive from yourself, and from the universe.
Jon Kabat-ZinnWhen people say "Let it go," what they really mean is "Get over it," and that's not a helpful thing to say. It's not a matter of letting go - you would if you could. Instead of "Let it go," we should probably say "Let it be"; this recognizes that the mind won't let go and the problem may not go away, and it allows you to form a healthier relationship with what's bothering you.
Jon Kabat-ZinnMindfulness is a way to rebalance ourselves. Instead of being lost in thought, or caught up in emotional upheaval, we can tip the scale in the direction of greater equanimity, clarity, wisdom, and self-compassion by actually learning how to inhabit that other dimension of our being.
Jon Kabat-ZinnScience is now documenting that it's not the objects of meditation that are important, it's the process of paying attention to them - the attending - that actually influences the organism in a whole range of different ways. The brain changes significantly enough to impact thought, emotion, and other biological functions. Today, people recognize that they're not going to find well-being from the outside, or from a pill; they're going to find it by looking inside. All the suffering, stress, and addiction comes from not realizing you already are what you are looking for.
Jon Kabat-Zinn