The first and most important thing is deep and sincere prayer. Ask Our Blessed Mother for her intercession and recite the rosary in her honor daily. Another prayer That is very special is the Anima Christi. You can find it in any Catholic prayer book.
Also The Confiteor is a good prayer to pray every day:"
I confess to Allmighty God, to blessed Mary ever Virgin,to blessed Michael the Archangel, to blessed John the Baptist, to the holy Apostels Peter and Paul, and to all the Saints, that I have sinned exceedingly in thought,word and deed, through my fault,through my fault, through my most grievous fault.
Therefore,I beseech blessed Mary ever Virgin, blessed Michael the Archangel, blessed John the Baptist, the holy Apostels Peter and Paul, and all the saints, to pray to Allmighty God for me.
May Allmighty God have mercy on me, forgive me my sins, and bring me to everlasting life. Amen.
May the allmighty and mercyfull Lord grant me pardon, absolution, and remission of all my sins. Amen."
Prayer has to be combined with action. So do active penance by serving the Lord in any capacity he calls you to.
Overcoming sinfull tendencies is a big challenge, but never give up trying. Our Lord will guide you.
My prayers are with you.
God love you!