。
In the morning, you wash your face, get yourself presentable, and then come here.
Literal
Morning [topic-は] face-washing [topic-は] of-course personal-appearance [object-を] tidying [from-てから] here [to-に] gather [copula-んだ].
洗顔はもちろん ('face-washing goes without saying') uses はもちろん ('of course, not to mention'). 身だしなみを整える ('to put one's appearance in order') is a set phrase for grooming and looking presentable. ~てからここに集まる ('then come/gather here') sequences the actions. んだ adds the explanatory force of a rule being laid down. Someone (a dorm supervisor, military instructor, etc.) is establishing a morning routine.