What do Muslims visualize when they worship God?

We do not visualize God, because if we do so we can only but visualize His creation. We can only visualize things which we see or perceive through our sensory perceptions. Hence, if we are asked to describe something or to visualize it, we do so in terms of other created things. Similarly, if we attempt to describe Allah, after we visualize Him, we end up describing His creation and not Him. Hence, the attempt to visualize Him is erroneous in itself. It is commonly believed that God is a ‘spirit’. However, this is incorrect because the spirit is a thing which is created and has been described by people similar to other created things. Allah is worshipped by knowledge of His attributes, not by visualizing Him. If one says a ‘piece’ of god is found in him, then it is not difficult for one to claim that ‘God’ is ‘more concentrated’ in him than others, hence promoting creation-worship.