Thanks, bonkydog!
How do you describe harm for PCs? I'll give you three answers. But consider, first, that harm for PCs isn't strictly related to the fiction, the way it is for NPCs. One PC could be in a horrific accident, lose a hand, and break a leg, and have one segment marked on their "clock" (because they received care from an Angel, for instance, and now the harm is gradually healing). Another could be in perfectly good health, as best we can tell, in the immediate sense, but have three segments marked off (they got knocked around in a few bar fights, so they have a black eye, but it's been a few days and the harm's not getting better on its own). I was sitting still when someone stuck a bloody axe into my leg for 2-harm, whereas you took a couple of punches in a friendly bareknuckle boxing contest (twice, for 1-harm each time) - do we "look" the same, on screen? Surely not.
Usually, it corresponds to their general physical state, but not necessarily - segments of the clock are an abstract measure of how close they are to death, rather. (Hence the "countdown clock", as opposed to a "health meter" or some such thing.)
Ok, three answers:
1. Ask the PLAYER to describe it to you. There's no downside here, and the player gets to characterize their PC a little further.
2-harm for the Faceless might mean to the player gruesome wounds and blood everywhere - but he just keeps on coming! Terrifying!
2-harm for the Battlebabe, though, running around nearly naked and with Impossible Reflexes, or the gorgeous Skinner, might be a singe on their upper arm where a bullet nearly got them - and the hole in their outfit just makes it look even more eye-catching.
It's a great opportunity to learn more about the PCs and how their players perceive them, stylistically speaking.
"So, you took 3-harm in those last couple of scenes. How are you holding up? Does it hurt like a bitch, or are you in shock, not even feeling it? Do you look like a mess?" That kind of thing is a great question.
I've seen some people write down a line of description next to each segment of harm they take. It serves as a nice reminder of what's happened to your character and how you might play them in any given moment. ("Hmmm, I see I've got a black eye and a bullet to my right shin. I'm probably limping a bit and my face is swollen from last night's debacle. I'm swearing a lot more than usual, too!")
2. In terms of AW's rules, the part of the system which comes into play here is two-fold:
First, note how harm gets better and worse at different points on the clock. This means certain things for your descriptions. For instance, if a punch in the stomach takes me past 9:00, we know the harm is going to get worse with time. That means something bad happened - are you coughing up blood now? It's not the same as 1-harm taking you from 12:00 to 3:00. We have to explain why it's going to be getting worse with time.
Second, the main source of description and detail for harm isn't the harm clock. It's the
harm move.
When you make that move, it tells you all kinds of things about what's going on - did you get knocked over, stunned, incapacitated by pain, or what? That's where you should get your description from.
3. If you want more than that, a while back put together various alternatives to AW's "hit points", which is more descriptive, visual, or "visceral". It works pretty much the same way as AW's system in terms of when character's die, but really brings the fiction into focus. Here's one which a lot of people liked and have been using in their AW games (I get some happy reports now and then):
http://ihousenews.pbworks.com/w/file/fetch/63408904/Apocalypse%20harm.pdfSometime later, another fellow wrote an even more detailed version called "Blood & Guts". You can do a search for that one, too, if you like!