Thank You Letter To Coach Letter To A Swim Coach..?

Letter to a swim coach..? - thank you letter to coach

I asked many questions about this already, but I really have not found an answer .. also in the attempt, my coach, write a thank you card to ... Can you tell me what you think:

Dear Coach,
I just wanted to write you this letter to thank him.
Thank you for all the time and effort you took notice of us.
Thank you for making me a better swimmer and a good coach.
And I thank you for motivaiting me and told me that I do it! (:
I have learned more confidence in myself and I've learned to think positively.
Coach thank you very much (:

Is that good? What can I add or what would someone please help me change! (And when should I do? "Last day of school, or as soon as you can throughout the season too long ...

Thank you!