Comparing with my English writing and Japanese writing

Umm, I have two problems in my English writing comparing with my Japanese writing. First, I don’t have enough vocabularies to express fully my idea and thought. That is so annoying for me because I have a lot of ideas and thoughts to output into the world. Second, I take much time to write in English. "Don’t hurry, Yohei! Practice will make you a good writer.” I hear that sentence from somewhere.