The fool has said in his heart, "there is no God".
When you see a painting, how do you know there was a painter?
well, the painting itself is proof there had to be a painter. You couldnt ask for better proof that there was a painter than the painting itself. You dont need to be a rocket scientist to understand, you just need eyes that see and a brain that works. It goes like this " painting...duh...painter" I call it the "duh" principle.
When you see a building, how do you know there was a builder? Again, you couldnt ask for better proof that there was a builder than the building itself.
The same hold true for watch- watch maker, automobile-automobile maker, t.v.-t.v. maker, micro wave oven - micro wave oven manufacturer. Anything with design and purpose has a designer and creator.
When you look at Creation - how do you know there was a Creator ? ... Duh.