Whichever is the less dominant hand. Just think of it this way, how often do you need your left and right hand throughout the day? If in your case you use your left hand much more often because you don't write much anyway, wear it on the right hand. Otherwise use it on your left.
most righties wear it on their left and vice versa i believe. if i were you id wear it on your left hand just because i feel like it might get annoying with writing, I don't know. try it on each wrist for a day and then decide which way you liked it better. you can always change it later :)
There was a similar question last night and someone gave a good answer you should use hand you are less active with since you write with your right I would wear it on left - The watch would bang off table as you write if you wore it on your right.