The Trades page lists every trade you currently have open. When there are none it says No trades open.

Search by the other character's name to find one quickly, and Clear search to see them all again.

Trade opens Trade with a player, where you pick who to trade with.

The button is unavailable once you already have a trade open with everyone else at the table, because you can only have one trade running with any given player.

Add Items opens Add Items to Trade. Pick an item and it appears on your side.

Each item on the table has Change quantity for offering more than one, and Take off the table to withdraw it.

An empty side reads Nothing offered yet, so it is always clear whether the other player has put anything down.

Money opens Money to Trade, where you set how much of each coin you are offering.

Money and items sit on the same side together, so one trade can be goods, coin, or both.

Confirm signals you are happy with the offer as it stands. The button then reads Confirmed, and pressing it again withdraws your confirmation.

While either side is confirmed the offer is locked: the money and item controls are unavailable, so nothing can change underneath someone who has already agreed. Unconfirm to edit.

Once both sides have confirmed, the button turns green and reads Complete. Completing asks Complete this trade?, and only then does anything actually change hands.

End Trade closes the trade with nothing exchanged, after asking End this trade?. Anything either of you put on the table stays where it was.

Use it when a negotiation goes nowhere, and it is the way out that costs neither side anything.

On a small screen the two sides do not fit side by side, so a switch appears to swap between your offer and theirs. Each side of the switch shows whose it is, how many items are on it, and whether that side has confirmed.