Definition of "unshit yourself" [Urban Dictionary]:
It is a Portuguese expression, translated to "desenmerda-te!", that is used when you want to say to someone that they're stuck in the mud and they need to sort their stuff out.

Example:
"Não há comboio hoje? Vens a pé! Desenmerda-te! Tens de cá vir ter" <-> "Is there no trains today? Come on foot! Unshit yourself. You've got to come here!"