Here's a really insightful comment from CS Lewis on praising God and why it's so important...
”I think we delight to praise what we enjoy because the praise not merely expresses but completes the enjoyment; it is its appointed consumation. It is not out of compliment that lovers keep on telling one another how beautiful they are; the delight is incomplete till it is expressed. It is frustrating to have discovered a new author and not to be able to tell anyone how good he is; to come suddenly, at the turn of the road, upon some mountain valley of unexpected gradeur and then to have to keep silent because the people with you care for it no more than for a tin can in the ditch; to hear a good joke and find no one to share it with.” (CS Lewis p.81 Reflections on Psalms)
Praise is necessary for us to complete our enjoyment of God. How often we can find that, though lethargic and spiritually dry, in the actual discipline of praise we find our joy in God re-awakened. So, praising God has this paradoxical impact on us - it makes us see just how great He really is.