Depending on where the earth is when you're born your personality is influenced by 1 of 12 signs. Zodiac signs aren't meant to be taken seriously, but surprisingly reflect on your actions and behavior, to a certain degree. Everyone is different even if you have the same Zodiac sign. These signs influence, they do not label. For example a Pisces will be influenced by its sign to be very emotional and dreamy, however this person has the ability to choose whether or not they want to go about with these instincts. A Gemini on the other hand, for example, will never share these traits, but might not fit their own sign very well either. It all depends on the individual. This is often why people dismiss zodiac signs as superstitions. Some will match their signs perfectly, some wont. These descriptions are sometimes general and vague but for the most part, correct.
It is said that Zodiac signs determine how old your soul is, with aries being the youngest and pisces being the oldest. Regardless if this is the case or not, it might make it easier for someone to understand them if you think this way. Say a Cancer is the teenager of the Zodiac signs, not all teenagers are exactly the same, but they all usually have the same intentions. For example, dating, sports, getting in trouble, video games, hanging with friends, some will rebel, some wont, ect. Each teenager is different, but their all pretty much on the same boat. This is a great way to think of Zodiac signs, not every Cancer will be the same but just like teenagers, they have similar ways of experiencing life.