As to the pedaling, which I presume to be your primary concern:
Use your ear. At the most basic level, if the melody is obscured by a wash of bass and inner voices, change the pedal!
That having been said, experiment - make it an étude in pedaling. The outer sections are string quartet writing, and so the movement of the voices must be heard - but the melody must remain legato and cantabile. This means frequent and discreet pedal changes! The pedal does not have to come all the way up to clear sound, nor must it go all the way down to sustain sound. However, make sure you have as legato a fingering as possible - the purpose of the pedal here is to enrich the sound with overtones, not to connect the notes.
Be very careful with pedaling in the middle section to keep the chromatic voice leading as clear as possible.
The point: use the pedal abundantly, but do not let anyone hear that you are pedaling. In other words, pedal frequently, discreetly, and most of the time, shallowly. Remember: your ear knows what your foot needs to do, so listen to it!
Hope this helps -
JBM