When you're an astrologer and you're working with a client, you get to see their natal chart. This helps you with more than just the reading; it also shows you how to best deal with the client. You want to focus on three parts of their chart: Sun, Moon, and Mercury.
The Sun shows who you truly are, so from their Sun sign, house, and aspects, you can get an idea of the kind of person they are at their core. Sun in Aries and the 3rd house? They don't waste time, and they don't take anything too seriously. Sun in Cancer and the 8th house? They're emotional, and need to be handled more carefully. Sun conjunct Saturn? They want the whole truth, plain and simple.
The Moon shows how you emotionally react and what you need to feel emotionally secure, so from their Moon sign, house, and aspects, you know what to do and not to do to trigger a bad emotional reaction from them. Water sign/house Moons - be sensitive. Fire sign/house Moons - be light. Air sign/house Moons - be wordy. Earth sign/house Moons - be down-to-earth.
Mercury shows our communication style, so this is the point you want to pay the most attention to. Connect to their Mercury so they can understand you. Often, misunderstanding is where we go wrong, so zone in on their Mercury and try to merge their style with your own.
Mercury Retrograde in Aries: March - April 2018
March 2018 New & Full Moons
April 2018 New & Full Moons
Jupiter in Scorpio: October 2017 - November 2018
Saturn in Capricorn: December 2017 - March 2020, July - December 2020