S - subjective (what you see - swelling, discoloration, deformity, any other 'first impressions' like how they walked in or how they're laying.)
O - objective (measurements, what the pt reports like pain number and description (sharp, burning...), anything else the pt says
A - assessment (should be self explanatory, but I've only done athletic training SOAP notes, so I would put my ddx here like wrist sprain vs distal radius fx - not sure how this is done in the nursing world, but ask me in 8 months and I'll know)
P - plan (what you're going to do immediately, what's already been done, follow up details)
Hope this helps a bit!!