This is a great question and there are several things that the Bush administration did to show their conservative colors.
First, they were hawking when it came to foreign policy. As you well know we went into Iraq thinking that there were weapons of mass destruction, when there was none. I doubt that a liberal would have gone in. Diplomacy would have been the route. With Bush, like his father before him, the United States went to war.
Second, under the Bush administration there was little talk of raising taxes on the wealthy. This is one of the biggest differences. Now there is talk of getting rid of the 15% dividend tax rule. The Bush administration would not have touched this at all. Moreover, the Bush administration gave further breaks to companies, so that they would stimulate the economy.
Finally, we could also see this is his appointment of supreme court justice.