Use the Psalm as the structure around which you add your comments and so pray your prayer. The Psalms are great for this - try Psalm 103, 139 or 145 for starters. Use the Psalm as scaffolding for your thinking and praying - read through the Psalm a phrase at a time and use the phrase as a starting point for your reflections, your questions, your praise, your requests, your pondering.

An example from Psalm 103 to get you started:

Praise the Lord, O my soul
all my inmost being,
praise his holy name.
Praise the Lord, O my soul,
and forget not all his benefits
Who forgives all my sins have forgiven all my sins . . .
Reflective prayer
Lord I want to praise you with all that I am
Lord, all I am, totally, praising you
Lord, you are holy, your name is holy, holy is the Lord
O Lord, thank you for all that you are, Holy, Almighty, wonderful Lord
Lord, thank you, thank you for your love and your grace, thank you for Jesus, thank you that you