When you analyze the claim made by an author, what is your next step—after identifying the claim? Find the supporting evidence t
he author provides. Look for the article's main ideas and topic sentences. Read other articles that make similar claims. Decide if the reasons provided for the claim are good ones.
Rule of thumb is a guide or refs principle of some sort. For example, "as a rule of thumb, I do not begin big projects until the weekend." I hope this helps.