Although the priest is the main celebrant, everyone at Mass is or needs to be a celebrant also. Participate more fully by being prepared. Plan on arriving early for Mass - about 10 minutes before Mass is about right. You should get there without rushing and without having any compulsion to hasten away. Upon entering, you may be used to dipping your fingertips in holy water and making the sign of the cross. This is a reminder of your own Baptism in Christ and of a new fife in Christ that you are living today within the Church community. Since the Blessed Sacrament is present in our Church, you should genuflect before entering a pew. This is a formal gesture of respect. You should do this deliberately, to show reverence, and should bend the knee in the direction of the Blessed Sacrament. Many Catholics genuflect in hasty, improper fashion. For some this gesture means nothing.
Where do you sit? Select a location which will give you the best opportunity for participation in the Mass. Usually the front quarter of the church is your best place for seeing, hearing and participating. After entering the pew, kneel for a few minutes of prayer before sitting down. This is a valuable time for private prayer in the Lord's house.
We have all been baptized in Christ. We are, therefore, not alone. We are together in Christ's Mystical Body, the Church. And so we assemble as did our ancestors in faith on the day of our Lord's Resurrection. To remember and to renew just as He told us to do. And it is precisely in the Sunday celebration of our parish that we come together to honor God in this highest form of prayer.