SELLING PROBLEM

Can someone teach me how could i sell an item with bot. So i want to do the "Nulgath Larvae" quest , take voucher of nulgath and sell it how could i do it. Please help me i'm new on grimoire..

You must go under the "Item" tab and click the first drop down box, then put the name of the item in the box below the drop down box. Then just click add command.