The best method would be to use formal, clear and objective language.
Explanation:
Writing professional messages requires a certain level of formality. This is because the message will be received in a formal and conservative environment, so the use of slang and informal language is not appropriate. The best method for writing professional messages is to use a formal language with the correct use of grammar and to convey information clearly, simply and objectively. This shows how you have the mastery of communication and writing as well as showing that you are straightforward and not "tangling" to communicate.
