The single greatest thing a person can do is offer worship to God. Catholics do this daily at the Mass. The Mass is divided into four parts: the Introductory Rites, the Liturgy of the Word, the Liturgy of the Eucharist, and the Concluding Rites. 

During the first part, we begin with song and prayer that praises God, thanks Him, and asks Him for forgiveness. At the Liturgy of the Word we listen to the Scripture readings that have inspired God’s faithful for millenia, then a homily in which the priest or deacon shares what God has given him to say to His people, and then we all pronounce the core principles of our faith. 

At the Liturgy of the Eucharist, the priest stands in the person of Christ, taking the bread, blessing it, breaking it, and giving it to the people as the Body, Blood, Soul and Divinity of our Lord.  

At the Concluding Rites, there is a closing prayer and final blessing, where we are sent by God to spread the Good News of our salvation.