Let's start!
Plastic Surgery
The normal procedure for an operation is: put the patient under anesthetics (total or partial), then do the operation with steel instruments, sew closed, let it heal. At times there is add stuff and remove stuff in between. Actually, that's the normal procedure for any surgery.
Surgery on a Garou
Assume you're a normal Garou. All Garou have massive natural healing 1. Especially rage healing. They even regrow lost limbs if they don't die from them.
Garou can heal from most wounds without ill effect.
A human whose fingers are bitten off by a wolf will need
surgery, and will lose some function in those fingers (if she
doesn’t lose the fingers entirely). A werewolf can grow the
missing tissue and nerve connections back, even re-growing
his fingers if they cannot be reattached. 2
Yes, a male Garou that lost his junk to anything but aggravated damage and thus has a Battle Scar (Gelded 2) gets it back with the healing the rage gives them. What doesn't kill them, makes them angrier.
This comes with a problem: When not in their breed form, they also regenerate poisons like alcohol and anesthetics away like they are nothing 3. Yes, you can't get a Garou drunk unless he's a homid or you use awakened beer (Fianna and Get love that stuff), and unless a drug is Wyrm-tainted to a degree it does damage it is at best a stopgap measure on a non-homid. So... to put the Garou under for the procedure, they need to be a homid first - or you are dealing with someone you just can't sedate.
Ok, it's a homid, what next?
Now, we can put our Garou under and can do our stuff, even without silver knives. What next? Ok, our patient comes out of the OP with a nice set of new additions or subtractions. Maybe they had they wanted to look like Scaramanga or had their facelift, NipTuck, or whatever.
While they are in their homid shape, they heal. The good news: they won't get an infection in the wound. Otherwise, they heal like humans 1 and that means that the lethal damage from the OP will take the normal time for a Wounded to Mauled damage to go away. A month and some to three months total recuperation time is expected for the last signs of such an Operation to go away, so far so good. We can fool the doctor!
But woe if they shift during or after the healing! Then the supernatural healing kicks in and the body knits the body to how it should be. Lost fingers from having it in the bandsaw return under the rage healing (which hurts). But also, because Scaramanga-chest, face-lift, and NipTuck are not Battle Scars, and so they fix themselves, just like the lost finger 2.
IF this can be circumvented by spending one of the items you can have bound with the rite of talisman dedication is something you should ask your GM.
... But as Nepene Nep correctly notes, there is also the W20 players guide or rather Changing Ways. This offers for example the ability to suppress your own healing factor due to sheer badassery 4. By suppressing your own healing factor during recuperation surely you can make the new modifications stay! A full Nip-Tuck might be at minimum equivalent to a large Tattoo when it comes to invasiveness, with a roll of at the very least 8 needed as a result.
However, the very same book also indicates, that human medicine is seen as Un-Garou and the products of modern medicine are so deeply tainted by Wyrm, that they are not really an option for anyone but a Glasswalker, and even that will have social repercussions:
While some urban Garou consider human medicines worth the risk, the clear majority see all modern medicines as marked by the Wyrm or Weaver.5.
How to do Plastic Surgery on a Garou.
Inside Help: Garou/Kinfolk Doctor & Glass Walker company products
With the ability to suppress the own healing, a Garou or Kinfolk Artist and Surgeon that knows his trade could - with the aid of silver implements and maybe a healing gift or two - do a safe procedure. Good enough for a facelift, complex piercings, a Tattoo, or (awakened) Botox. Even gold teeth or such could be easily enough done...
This however leaves the question of the more invasive procedures that require an implant. The real problem is acquiring an implant that is not inherently tainted and at the same time has the required look and feel for what is wanted. Most likely, a Glass Walker company might manufacture such required implants in a Garou Friendly way. These specialty products - if available at all - might require payment of both money and favors.
In other words: For small procedures, you likely will find a capable doctor that can do it without putting you under and stay quiet. If you can get the required stuff for major facelifts is up to your Storyteller, but you can throw them a huge hook with your plan.
Inside Help: Rites
The rules for the Rites don't have an explicit rite that allows for such, but the Storyteller certainly might allow you to seek out someone that has a Mythic rite that could help you. It sounds like the Rite of Growth 6 could be a good base for working out something with your GM. If you find a Theurge that has such a rite, you might pay a mix of favor and cash to them. And then you spend the experience for the new attribute.
There you go! Give your GM a good story hook and ask him for a Garou-Theurge-Doctor that can make the spirits make you more pretty!
Outside Help: Mages
The possibly best way to alter the appearance of a Garou that is not battle scars is to find a Mage that has a high Life sphere. Because that is one of the only ways that can alter what should be. Which is altering the pattern in Mage-terms. Doing a magical operation certainly works, but it also might be an affront to your fellow Garou - you had an outsider mess with what you are and might certainly have repercussions. It also costs the experience and might give the mage a huge headache.
For rules on this, you need both the M20 and a short look into How Do You Do That 7. It requires the Mage to have Life 4, Spirit 2 to even begin.
Beyond Surgery
Appearance is more than just what you look like. It's also how you hold yourself and move. It's... messy. I strongly suggest looking at How to play Appearance straight and right? for more information on what is and what isn't appearance.
In case the surgery planned transgresses gender boundaries deliberately, Where do the Bête stand on LGBT issues? might be of assistance.
- W20 p.256
- W20 pp.259
- W20 p.258
- Changing Ways p.14
- Changing Ways p.15
- W20 p.210
- How do you do that? p.21