Why do you say one thing, and then go and do another? - ¿Por qué dices una cosa y luego vas y haces otra?
You say one thing and then act just the opposite. - Dices algo y luego haces justo lo contrario.
subsequently or soon afterward (often used as sentence connectors); "then he left"; "go left first, then right"; "first came lightning, then thunder"; "we watched the late movie and then went to bed"; "and so home and to bed"