To our mind, someone who wants other people to praise them is showing that they are either very needy people, or are totally full of themselves. Why is this not true of God?

I think it is good to approach this from 3 angles:

1. We like to praise people who we consider are worthy of praise
2. We like to celebrate great events or achievements
3. We feel it is right for the right person to get acknowledgement for what they have done.

There is a common theme here – we seem to be designed (created) to enjoy praising where it is due.  From this we can see that God wants us to praise him partly because it is good and pleasurable for us, rather than for his benefit.

So, looking at these in turn in more detail:

1. We like to praise people who are worthy of praise

One only has to look at the crowds that gather when the Queen is around, or to a lesser or greater extent, on Father’s Day, children want to honour their father. This is fitting and pleasurable for us.  In a similar way, since we have a heavenly King – a heavenly Father, and if we recognise who he is and what he has done, then we will delight in singing his praises.

2. We like to celebrate great events or achievements

In a similar way, when our team wins a grand final, we want to be in on the celebrations. That brings us great joy.  Likewise, when we see the victory that Jesus has achieved over Satan: outsmarting him by dying on the cross when Satan thought that he had won; and through that death dealing with our sins and slavery to Satan; then we will want to celebrate that great victory. That is only natural, and extremely pleasurable.

3. We feel it is right for the right person to get acknowledgement for what they have done.

If someone has achieved something magnificent, e.g. they produced a great work of art, and then someone else takes the credit, we are offended, and we want to right the wrong.  We also feel it is right for the artist to feel aggrieved.  It is the same for the one who created the universe.  We should feel offended if his work is attributed to someone or something else, and it is right for him to want to correct the record.  We would want to be in on the celebration when the court finds that he is indeed the author and he finally gets the recognition he rightly deserves.