How did David celebrate as the ark was brought into the City of David?

Answer: He danced with all his might

Wearing a linen ephod, David danced before the LORD with all his might, amid shouting and the sound of the ram's horn.

“And David, wearing a linen ephod, danced with all his might before the LORD, while he and all the house of Israel brought up the ark of the LORD with shouting and the sounding of the ram’s horn.”— 2 Samuel 6:14-15 (BSB)