You go to the Black Market and click on the Piece Of Cloud. Then you choose what horse you want to use it on, then hit apply. this will make you horse four months younger and credit oyur account 2 aging points to use on any horse.
A piece of cloud is a Black Market item. It is really rare. A piece of cloud makes your horse 4 months younger and gives you two aging points. It does not affect your horse's morale, energy, or...
You should generally only sell a piece of cloud for one pass, because that is how much it is at the black market. You could always go to the store, and then to "exchange items" and make an offer. It...