The attitude of a writer is reflected in the choice of words, the phrasing and the overall style and organization of the essay. What kinds of words and images are used? Kolin, Successful Writing at Work, Concise 4th ed.
You can usually find a tone by asking these three questions: Why am I writing this? In creative writing, your tone is more subjective, but you should always aim to communicate clearly.
Oxford University Press, Tone and Diction "The main factor in tone is dictionthe words that the writer chooses. How does the writer feel about the topic? In formal writing, your tone should be clear, concise, confident, and courteous.
If you need help coming up with more tone words, check out this list. Genre sometimes determines the tone. For one kind of writing, an author may choose one type of vocabulary, perhaps slangand for another, the same writer may choose an entirely different set of words.