From the human point of view, infinity means having no limits of any kind and omnipotence means unlimited power. In our minds they are two different aspects, but in God, they are simply bound up in His one nature. There is no difference between them. Strictly speaking they don't exist in separation from one another in God. It is only for our understanding that we explain them separately.
Perfection means utterly complete, having no defects or blemishes.
It can also mean being completely suited fo a particular purpose. We can see how inadequate human words are in explaining about God, and yet even the human word perfect can give us some insight into God's nature. It seems trite to say that God is completely suited for the particular purpose of being God, yet some prayerful reflection on this could help us to see great depth in these words. God's perfection lies in the fact the He is the absolute and complete fulfilment of any condition which could be placed on the role of being God. In one sense, this is like Him being, at the same time, both the definition of what is required to be God and the most perfect fulfilment of that definition.