The gates are representative of the entrance to a city or public place. We are to enter into the gates of salvation with thanksgiving. This deals with our public lives. The courts are representative of the home or abode. We could apply this to our own homes, but a better application would be the house of God.
Praise means heartfelt adoration.
Our thanksgiving should be personal to us. It should be heartfelt and moving. It is not an imitation or just an outward show of emotion. It comes from deep inside the soul, and merges with the Spirit of God. The final phase of the progression can be found here.