So many of us use the term "unconditional" when referring to the Divine, the Source, the God of your understanding. We have "faith" there is a Being out there who loves us unconditionally. Ironically, many faiths talk of an unconditionally loving God and then immediately impose limits on whom that God will unfold its unconditionally loving attitude. The practice of mindfulness is like "trying on" an unconditionally loving attitude.
Sit comfortably straight, pay attention to the breath and observe thought, emotion and sensation without judgement.
This could be the entire manual on mindfulness meditation. Volumes and volumes continue to be written on this ultimately simply subject and I am no exception. Our minds go to great lengths to avoid simplicity in favor of complexity.
Give yourself the gift of simplicity and practice being non-judgemental with yourself. There is a ripple-effect that will touch your spouse, children, co-workers, friends and family; even random strangers will recognize that simple presence when it is present. Try taking a God's eye view and attune your mind and heart to unconditional love. Just try it for a few breaths every day.