what you do
Más vale que sepas lo que haces.
You better know what you're doing.
Te digo yo lo que haces, no haces nada.
I'll tell you what you're doing: you're doing nothing.
— Los lunes al sol (2002)
You'll know what you're doing.
Sólo quiero que veas lo que haces.
I just want you to see what you do.
Think about what you're doing.
Lo que haces es más importante que lo que dices.
What you do is more important than what you say.
Espero que sepas lo que haces.
I hope you know what you're doing.