Here's a quick and dirty summary based on Lucretius. Everyone studying Epicurus should have a goal of producing a more accurate one for themselves:
1 - It's pleasure, not "gods," which serves as the guiding force and controls living things in the universe;
2 - Supernatural religion is the true source of most of the evil in the world;
3 - The universe operates naturally, with the ultimate proof being that nothing comes from nothing, nothing goes to nothing, and everything in between arises as the natural function of the movement of the atoms;
4 - The universe is infinite in size, eternal in time, and therefore was never created by any gods
5 - Life is not confined to this earth, but can arise anywhere the conditions are right, and there are innumerable places in the universe like Earth
where conditions are right. God(s) did not create the Earth as someplace special as their plaything.
6 - The soul is made of particles and just as natural as the body, from which it cannot be separate. When the body dies, the soul dies.
7 - Consciousness is based on sensation and ends at death. All that is good or evil comes to us through sensation. When our sensations are over at death, we are over. There is no reward or punishment after death. Therefore THIS life is the only one we have.
8 - Sensations come to us through the movement of atoms. In order to understand how our senses perceive things, we must understand the movement of atoms and how illusions can arise. Once we understand the nature of illusions and perceptions, we can have confidence about which of our conclusions are true, and which much await further information for more understanding.
With all these as the clear foundation of a philosophy, how could anyone conclude anything other than it teaches us that it is supremely important to use our time prudently to live the happiest life possible?
And at the end of your life, is such a person going to be happy looking back and saying to himself "I did my best to escape from pain?" No! It is "pleasure" - broadly understood - that is the beginning and the end of what life is about.