People tend to be like their favorite movie characters or idols. If you can know who and why, it will give your more information about personality.
Obviously look first at the left ring finger. Look for a ring, tan line, or any other anomalies on the ring finger.
Look at which hand watches are on. 85% of the time, righties have it on their left hand and vice versa for lefties. If wearing a belt, look for the direction the tail sticks out from. 99% of the time, righties have the belt sticking out to the left and vice versa for lefties (statistics based on personal experience).
Look for hair on their clothing. Pet hair on the upper part of a person generally means a smaller pet (i.e. easy to pick up and hold) and pet hair on the lower part could mean anything (this is extremely variance dependent: this is helpful only as an insight, not as a deduction).
Look for tendencies such as tapping fingers or feet, shaking legs, consistent rubbing of any parts of the face. Watch where their eyes are fixated at (or not at), how they walk, their posture, tone of voice, etc.
Not many of these will be helpful by themselves or without a large enough sample size, but, depending on the situation and circumstances, it can tell us a lot about a person.
Fanning lines will show you how they dress normally. A tan that stops above the elbow shows that the person wears t-shirts usually, which can give a clue about their life. Same goes for the left-hand-only tan (spends a lot of time driving), pigmentation around the eyes (wearing glasses), a white strip at the non dominant hand, left by a watch (a lost one, or if aged, then retired), the wedding band ring line.
Do they look uncomfortable? That can tell you a lot about their personality. Let's say it's a female and she's wearing a deep v-neck. Does she keep pulling it up, fidgeting with it? That would show if the person has some insecurities, if they care about appearance. A person with high heels. Do they have good balance? If so, then that means they wear high heels often, maybe because they are very social or just formal.
Shoes with high platform or high heels - means insecurity about her height
Dark colored clothes - means insecurity about her weight
Discomfort (muscle tension and aimless movements) - means insecurity about new or unwanted experience
Excessive politeness - means insufficient assertivity (accommodating personality type)
Excessive gestures and mimics - means they know each other very well
Smoke cigarette or have tattoo or extroverted - inclined to risk (risk-taker)
Richness of her answer to your question is very good indicator of her sympathy to you
Enother very good indicator of sympathy is her first glance in funny situation
Especially if the person is female. Do they bite them? If so, they are probably insecure and usually a perfectionist. Are they clean, manicured? If they have nailpolish, is it done well, is it smudged or is it obviously done by someone else? This can say a lot about person's patience or if they have good income