I play DCDCDC (hold the last C longer and then do)......DE. If your fingers are not fast yet, this part is very annoying and if you do not play well, this part really really ruins the piece. The more you practice, you will be able to play the trill easily.
The key is to play the four notes prior the trill (EDCB) lightly and smoothly, and then do the trill lightly too.
By the way, this piece is extremely difficult to play well and musically. That is why many professional uses this piece as their competition piece.