1.
If you do something up, you fasten it.
Mari did up the buttons...
Keep your scarf on, do your coat up.
PHRASAL VERB: V P n (not pron), V n P
2.
If you ~ an old building, you decorate and repair it so that it is in a better condition. (BRIT)
Nicholas has bought a barn in Provence and is spending August doing it up.
PHRASAL VERB: V n P, also V P n (not pron)
3.
If you say that a person or room is done up in a particular way, you mean they are dressed or decorated in that way, often a way that is rather ridiculous or extreme.
...Beatrice, usually done up like the fairy on the Christmas tree...
PHRASAL VERB: usu passive, be V-ed prep/adv