https://www.sylestia.com/view/pets/?petid=8420636:2500g

Hello! I'd like to buy your night sky nytekrie seed =) Can you send a mushroom for this?

Mushroom?

Yeah, the Fairy Mushrooms are the easiest way to send payments for items that you can't put a payment on when trading (like seeds and catas) since they're an item most people have and don't really use. So, in your inventory, if you click on your Fairy Mushroom (you should have a few from playing the main quests), then the coin stack icon at the bottom (should say "Split Stack Into Multiple Stacks" when you hover over it), and then an empty spot in your inventory, you'll get prompted to enter the number you want in this stack (How many stacks do you want to split?). Leave the default of 1 in the box and click "Split". This will give you 1 Fairy Mushroom in it's own spot. Click this Fairy Mushroom and then the envelope icon at the bottom with a green arrow (should say "Mail Item to Player" when you hover over it). Put my name in the Recipient box and enter the amount you want to bill me in the "CoD Fee" box. I'll accept the trade and send your mushroom back. Then you can send the seed to me from the Festival Garden page =) Lemme know if you have any questions!

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Like Hauntedmist described, but maybe pictures are more helpful, there's a guide here for that! :)

thx