8) Refrigeration
Bear in mind that most cakes are at their best within a day of their creation. You can certainly make a cake two days ahead (it won’t ruin the party), it just won’t be at its best.
It is always best to leave the cake out UNLESS it has an icing/filling that will go bad (i.e. whipped cream or cream cheese). If iced with buttercream or fondant, just keep the cake wrapped/covered well so it doesn’t dry out. The cake ingredients are cooked so don't worry about eggs going bad or anything. In fact, the original purpose of icing was to keep cakes moist.
Refrigeration involves dehumidifying the air in order to cool it. As such, refrigerating a cake is generally not the best choice as storing in the fridge will dry a cake out and cause it to taste stale sooner. Even well covered cakes will dehydrate to some degree in the fridge.
Another note is condensation that accumulates on items stored in the fridge may have undesirable effects on your decorating.
I never refrigerate my cakes. I usually make them within 24 hours and don't use cream cheese or whipped cream frostings. And they haven’t failed me yet!