Try getting a book called Roget's Thesaurus. It give synonyms for words. And, you can use the book to enrich and color your vocabulary. Also, if writing a letter, run it by a close friend and ask them to help you to compose.
Think before talking and take your time to plan something out. Reading the great words of writers and poets has helped me become a more articulate person.
Wise men think before they speak. Men of few words are respected. Every word spoken adds to your personality. It's wise not to talk at all than speaking foolishness.
