Sometimes I am at a complete loss for what to pray. The cool thing is the Bible is a rich well, full of examples of prayers to God. Here is a great prayer from the Psalms dealing with sin:
Psalm 19:12–14 (ESV)
12Who can discern his errors?
Declare me innocent from hidden faults.
13Keep back your servant also from presumptuous sins;
let them not have dominion over me!
Then I shall be blameless,
and innocent of great transgression.
14Let the words of my mouth and the meditation of my heart
be acceptable in your sight,
O Lord, my rock and my redeemer.
So when you get stuck or you feel stale in your prayer life, spend some time reading the Word and incorporate it into your communication with the Father. Pray the Word!
Father, thank you for another day. Thank you for your Word and the opportunity to worship you and commune with you in prayer. Remind us of your love for us and of the adoption we have into your family through your Son. Thank you for your many blessings. In Jesus name, Amen.