The Universe is a fascinating topic. How the universe was made can be traced back to many things, I don't wish to offend anyone, but I will not be talking about any divine powers, just some scientific theories.
Most Theories start with a big bang of sorts. The big bang is really more of a cosmic stretch of the universe. Most people know about the big bang or at least the basics, so I will proceed to other theories about the origin of the universe.
The first theory involves another dimension. The idea is that our universe is a 3-D ball bouncing around in a 4-D plane. We are not the only 3-D universe in this plane and these "balls" collide. This collision is a new 'big bang" and the cycle goes on. This would mean that the life of our universe expands and continues until it resets by colliding with another. There are flaws with this theory, like how can the balls be expanding because we know the universe is, what is the limit to the size? Also, it addresses nothing with the 4-D plane, we have no limits for that.
Another theory is a similar one, dealing with the 4th dimension. This one says that the universe is constantly expanding and in doing so, thins out. The universe is created by the implosion of a 4-D star, and thins in 3-D until it creates the foundation of another universe. This theory explains the expansion and accelerating of the universe but again fails in any justification for it's 4-D claims.
Lastly is the most abstract theory. This theory doesn't address the creation of the universe but addresses the idea of time itself. It is the idea that there is no past or future just a series of moments. Our perception of time is just the progression of these moments. By this theory, the origin of the universe is irrelevant because time itself doesn't exist, it's just a perceived illusion. I personally don't like this theory because it's impossible to prove, but it makes you think.