There are two main ways to decide what political party you think you would like to join. The first is easier and quicker, but somewhat less help in allowing you to decide. The second gives you better information, but takes longer. Since you typically ask questions about Australia, I will discuss this using examples from Australian political parties.
The first way to decide is by looking at information given out by the parties themselves. Today, the best way to do this is by looking at the party’s website. This can give you a lot of information rather quickly. The problem is that the parties make their websites fairly unspecific. They want to say things that sound good to everyone and don’t offend anyone. So, for example, the Liberal Party says that they believe
In equal opportunity for all Australians; and the encouragement and facilitation of wealth so that all may enjoy the highest possible standards of living, health, education and social justice.
It is hard to imagine any party that does not believe in this and, therefore, party websites can be less helpful in making your decision.
The longer and harder way to decide is by paying attention to the news for a while. Since Prime Minister Abbot took office only recently, there should be many articles from the last two weeks or so about what he and the Liberal Party want to do. If you read or listen to political news, you should quickly get enough information about the positions that the parties take on various issues. This will be your best way to determine which parties have policies that feel right to you.