Here is a helpful examination of conscience, based on the Ten Commandments. Perform a brief examination every night, but go through a more thorough examination before confessing your sins to the priest.
The Commandments of God
Have I recommended myself regularly to God? Neglected my morning or evening prayers? Omitted my religious obligations because of human respect? Presumed upon God's mercy in committing sin?
Have I read books or papers opposed to the Church and her teachings? Did I make use of superstitious practices; such as believing in dreams, and charms, and the like? Have I spoken irreverently of persons (priests or religious), places (e.g, the Church), or things (the sacred vessels) which especially represent God?
Have I used my authority over inferiors properly? As a parent, by good example in the home and by sending the children to a Catholic school? As a person in public office, by promoting the common welfare? As an employer, by being considerate of the employees?