Instructions
Study the different astrological signs. You will have to know these well to be able to make any real guess at someone's sign. Pay attention to the character traits and personality qualities that are associated with each sign.
Examine the signs of the zodiac, and memorize these characteristics:
Look for blatant qualities in the people you are trying to guess. For example, if you are trying to guess someone who is loud and wants to fight, your first instinct might be to think Aries.
Study the person's appearance looking for any characteristics that you can identify as associated with a particular sign. You may or may not find these, depending on the person you're looking at.
Familiarize yourself with the different elements as they are associated to astrological signs. Fire, earth, wind and water make up the four elements and you should probably know all the characteristics associated with them before trying to guess someone's sign.
Continually observe your subject for a while and compile your data. Start trying to put the person into a category, perhaps narrowing it to two or three probable signs.
Make an educated guess based on all of the above information you have amassed about your subject. Believe it or not, you will actually get better over time.
Aquarius - Easygoing, creative.
Aries - Initiator, starts trouble.
Taurus - Materialistic but appreciative.
Gemini - Informative, likes trivia.
Cancer - Likes family and groups.
Leo - Reliable and strong.
Virgo - Analytical and scientific.
Libra - Works well with others, cooperative.
Scorpio - Emotional, likes challenges.
Sagittarius - Searches for meaning, philosophical.
Capricorn - Likes order and rules.
Pisces - Enjoys civil disobedience and the divine.