<span>gathering information </span><span>questioning the speaker's reasoning </span><span><span>reflecting the speaker's thoughts and feelings</span> </span>
You obviously need to gather information coming from the speaker. Besides that, you have to question the speaker's reasoning to make sure that his logic is or isn't sound. You need to be able to separate what makes sense from what doesn't, which brings us to the last one: reflecting the speaker's thoughts and feelings. After all, you have to think about things in a meaningful way to be able to criticize correctly.
Whenever you're leaving a phone message, you should speak clearly, spell your name, state your purpose, and: C. Leave your phone number. That is the professional way. Hope that helps.