You want to pray with more heart. So do I. One way of growing in this endeavor is to take a prayer of the Bible and put it in your own words. The following is my way of re-praying Psalm 139 (written by King David 3,000 years ago).
Lord, you know everything about me.
You know when I sit down and when I get up.
You know everything I think and everything I say even before I say it.
You are intimately aware of what I do and why I do it and still you love me.
In every circumstance, you go before me and behind me.
The gentleness of your touch guides me.
You think about me all the time, even at night while I’m sleeping.
When I am ashamed or angry and want to hide from you, still you are there.
If I traveled to the farthest galaxy, you would be there waiting for me.
Thank you, Lord!
These truths are so wonderful that they are beyond comprehension.
They stir my soul and make me love you more.
Search deep inside my heart, O God, where all my worries live.
Show me anything that is not worthy of you and lead me in your ways forever.