Read the book, he explains his approach pretty comprehensively. I'm not going to summarize it here.
Just another evangelist
Richard Dawkins said:* Atheists can be happy, balanced, moral, and intellectually fulfilled.
* Natural selection and similar scientific theories are superior to a "God hypothesis" — the illusion of intelligent design — in explaining the living world and the cosmos.
* Children should not be labelled by their parents' religion. Terms like "Catholic child" or "Muslim child" should make people flinch.
* Atheists should be proud, not apologetic, because atheism is evidence of a healthy, independent mind.[1]
He's a poor philosopher and as such his arguments appeal only to those who are as ignorant as he is.
Plantinga, an analytic philosopher and advocate of (Christian) theism and modest version of intelligent design, has published a detailed review titled "The Dawkins Confusion". He says that Dawkins is a "brilliant writer" but that this book is nothing more than an "extended diatribe [...] and contains little science", claiming that "many of [Dawkins'] arguments would receive a failing grade in a sophomore philosophy class." He concentrates on Chapter Four, "Why There Almost Certainly is No God", by saying that Dawkins' argument is that because the Universe has so much information in it that a hypothetical creating God would have to be enormously complex and thus enormously improbable. Plantinga claims that Dawkins does not support this assertion and suggests that Dawkins is assuming materialism. Plantinga states that the book's argument "...really doesn't give even the slightest reason for thinking belief in God mistaken, let alone a delusion".[22]