ok this is the easiest way for me but there are others. go to falconreach and go to the inn. Click on serenity and a whole lot of icons should come up along the bottom of the screen. Click on the one that sez shop. once the shop data loads, look up the top and next to the word buy there should be the heading "sell". now a list of your own inventory should come up.Simply select the item that you wish to sell and look underneath the description for a buton that sez sell. Click on it and taadaa you have sold it
lol hope ths helps.
I am new to this so i am not very good at answering yet