I have previously shared prayers adapted from Psalm 62 and Psalm 8 that we have used at our high school prayer breakfasts on Tuesday mornings. Here's one we recently prayed from Psalm 103:
Lord, we bless You.
With all that is within us, we bless You.
We bless You and we do not forget all your benefits:
You forgive our sins.
We are thankful that You do not deal with us according to our sins.
We are thankful that You do not repay us according to our sins.
For as high as the heavens are above the earth, so great is your steadfast love for us.
As far as the east is from the west, so far do You remove our sins from us.
You heal diseases.
You redeem lives from the pit.
You crown us with steadfast love and mercy.
You are good.
Lord, You are merciful and gracious, slow to anger and abounding in steadfast love.
Lord, we bless You.