Making a separate Trade panel would help focus the different sections of the game and would allow further improvements, such as:
1) Trade type selection
The player would select the appropriate trade option: 'Want to Sell' (WTS), 'Want to Trade' (WTT) or 'Want to Buy' (WTB).
2) Trade type placement
The different types of trade would then be placed in different sections. Each of these sections could be collapsible (saving screen space) and the player could focus on what's important at a given moment, making things less confusing.
3) Enter the Item(s) of interest
Just after the trade type selection, there could be placed the following interface:
a) "Type the item's description (1/4):"
b) That description would then be added into a collapsible tab of up to four descriptions.
c) In that tab, there would be simple options to remove or edit a description or to remove all.
d) Those descriptions would rotate automatically on the players advertising place, which would operate in the same way as it is today.