Best time to ice the cake?

[Gigondas]

Being lazy and got ready made marzipan and icing this year. When is best time to ice it- day you want to eat it or day before? Also do any of you put cake out on wire rack while sorting icing (mine is quite well fed so a little moist but I guess that doesn't matter as will help marzipan stick and no one likes dry cake).

This is my first year making my own cake, but I marzipaned one at the start of the month and the other today as the marzipan needs time to rest or something and am icing them tomorrow as ds and dd will both be at the cm's to give me time for last minute Christmas things.

Thank you- I knew there was something on timing had forgotten. Will marzipan tomorrow then

Sadly dd hear with me- think its fair to say with her help it wont look like the one jn the book