First, let me define some terms. Reality: the totality of existence. Therefore, the negation of reality is non-being, not anything, or literally nothing.
Let us say that we are part of an apparently designed reality that arbitrarily exists. By apparently designed, I mean it behaves in an intelligible way: it is filled with intelligible processes. Our reality is neither chaos nor random. If it were, then science would be impossible, and we would not exist. An apparently designed reality seems to me to be more plausible given theism because if atheism were true, then I would expect reality to behave in an unintelligible and random manner. Actually, I would not expect it to exist at all, but I am getting ahead of myself. How would chemistry, biology, mathematics, physics, etc., exist in such a reality? Put another way, is an unintelligible reality more likely given atheism or theism? Perhaps you disagree, but an unintelligible reality seems more likely given that atheism were true. Yet, we find ourselves in an intelligible reality.
So, we exist in this apparently designed reality that arbitrary exists. Did it always exist? I know that some people believe that time is interwoven with the universe, but is that true for all existence (reality)? Let us say that it is. That would mean we could never ask was there a time before reality? But this just an exercise in semantics to avoid a big question: did reality come out of non-being, uncaused? Perhaps that is not what happened. Perhaps reality is past-eternal, like how God is described in the Bible.
If our apparently designed reality that arbitrary exists is past-eternal, then how did the present arrive? As I mentioned before, reality is filled with processes. It is filled with events. How did an actually infinite number of processes and events occur, followed by the present? At the very least, this appears to be implausible. Therefore, it would make more sense to assume that reality is not past-eternal. But that brings us back to the idea that reality came out of non-being, uncaused.
So... help me out here because atheism as a worldview appears to be retarded.