I believe in a God, Supreme Being, Higher Power or whatever you want to call.
How is it that the Universe exists, and that everything was perfectly made?
Let's first define the universe, and the implications of said definition.
The Universe: The totality of all existence.
This means that the Universe encompasses all of existence over the things that actually exist. This includes God, provided that he actually exists.
So, how did the totality of all existence, or in short, existence come to be? There are only 2 answers: existence had a beginning, or it is the case that existence had no beginning.
If existence had no beginning, then this implies that existence has always existed.
If existence had a beginning, this does not necessarily mean that something created existence.
Now, if existence had a beginning, it cannot be created by an existent (something that exists). This is due to the contradiction because if something where to create existence, it would imply that existence had already existed for the existent to create existence. Now, since God is considered an existent (something that exists), he cannot be the creator of existence, or, The Universe.
If we reject that existence had a beginning, then it means that the other alternative is that existence has always existed, which means that adding God into the equation is an extra complication.
As it stands, I don't believe in the existence of God because there is no empirical evidence that supports the existence of such a being. In addition, popular conceptions of God say this being has contradictory attributes which violate the law of non-contradiction, thus, these conceptions of God most certainly do not exist.