Any particular part?
Be sure to speed up in the 3/4 mazurka-like section, or else it just drags.
Work on the scales at the end carefullly, especiallythe 35:4 one.
And this is a good idea I found out by accident:
Listen to Chopin's Piano Concerto No.2 in F minor. This nocturne was kind of like a melting pot for the ideas he eventually used in the concerto. The mazurka section in the nocturne becomes the dance in the middle of the 3rd mvt., the Adagio arpeggio is the last measure in the 2nd mvt., and if you listen closely, there's a lot of other direct parallels.
Listen to how the pianist plays those sections, and it should give you some ideas on how to interpret them in the nocturne.
Phil