I want to write a children book

I plan to write my own children book by this year.  

I have some ideas in my brain but I have problem to transform the ideas to beautiful words.  My English writing skills is very poor.  I am not a good author and I need to improve my writing skills before I start to write the book.

The story of my children's book is about a magical whale.  I had draw the illustration for my children's book idea.  I put this picture as the title background photo of my blogger to remind myself about this project.  

I plan to self-publish my book but I don't have enough budget to do so.  Therefore, I am doing freelancer job now as an illustrator for children's book.