Another tricky question is where to put pronoun in a sentence with imperative form of pronominal verbs (verbs with 'se'), such as se laver (wash oneself)
At first recall the conjugation of such verbs:
je me lave nous nous lavons
tu te lave vous vous lavez
il se lave ils se lavent
Je ne me lave pas.
And here are imperative forms:
And here is the list of mostly used pronominal verbs.