Someday we'll all be full of grace; Mary was the first to receive this gift, and she is a model of what God has in mind for all of us. GRACE is all the gifts of God, both natural and supernatural, which He provides to us because of His mercy. Note: It's available to us because of what Jesus did for us on the cross, not because we've earned it! We haven't earned it! To become the mother of the Saviour, Mary "was enriched by God with gifts appropriate to such a role." The angel Gabriel at the moment of the annunciation salutes her as "full of grace" (Luke 1:28). By her complete adherence to the Father's will, to his Son's redemptive work, and to every prompting of the Holy Spirit, the Virgin Mary is the Church's model of faith and charity. Thus she is a "preeminent and . . . wholly unique member of the Church"; indeed, she is the "exemplary realization" of the Church (Catechism para. 967). When we realize we have sinned, one reason why it is better to go to a priest for the Sacrament of Reconciliation than to go directly to God alone in prayer is because of it is a sacrament, and sacraments are doors that open us to grace. Sacraments are the in-pouring of God's grace. This grace gives us supernatural help to avoid the same sin in the future. For sin shall not be your master, because you are not under law, but under grace (Romans 6:14 NIV). When we sin, God's mercy restores us to grace: And the God of all grace, who called you to his eternal glory in Christ, after you have suffered a little while, will himself restore you and make you strong, firm and steadfast (1 Peter 5:10 NIV). God is very gracious. In His generous love for us, He offers us everything we need to resist sin. Having grace means receiving all the gifts of God that we need: From the fullness of his grace we have all received one blessing after another. For the law was given through Moses; grace and truth came through Jesus Christ (John 1:16-18). Each gift we have is a grace! Mary was full of grace and that means she was full of God's gifts. http://wordbytes.org/SpirGrowth/grace.htm

I'm not exactly sure how to explain it, it's with the holy spirit, like, the holy spirits with you. like when you do one of the 7 sacrements, the holy spirits with you, and you are full of grace... that's the best i can describe it..