yep i go the brazilian regularly - def get it done by a professional.. hurts less, better result etc.
i would trim if going the braz - it hurts less and is easier for them. they may trim it for you if you dont do it yourself. the more often you do it (without shaving in b/n) the less growth and less pain you will have next time (and results last longer as you dont get all the diff lengths ).
if you are just tidying up sides (for now) you will leave undies on and pull them to the sides...
best of luck!