I am a total noob when it comes to wig-styling - I've managed okay with the two other wigs I'm taking to Aya, but this one I'm really not sure how to tackle and I would really appreciate some advice:

Fuuka Yamagishi - Persona 3 FES

As you can see, she's got a really choppy hairstyle, very boyish. And I have
this wig to modify.

I would imagine it would be really, really easy to ruin a wig trying to achieve this hairstyle - any dos or don'ts that anybody can tell me before I get started on this? I'm thinking doing it in sections and wetting it would be a good idea but anything else I'm not really sure about.

Thankyou!

you will need to get it cut alot shorter as you can see she has a very short fringe and the length needs to come up a bit and all the layers need to near enough match the fringe but getting longer to the sides

the only other thing i can think of is to doble ot over and tuck it underneath its self and use a strong spray and scrunch it to get the texture

The key to that kind of hair style is to know where on you the wig reaches.
Cutting it isn't too much of a problem, you need to use vertical rather than horizontal cuts and work up gradually. Always cut lower than what you need to begin with, it gives you space to make mistakes and still fix it. It's a nice simple style so you just need to trim the fringe and cut the rest into a straight bob. That wig is layered already so you won't have to worry about that bit.
Getting it wet isn't needed really, as long as you cut carefully it's fine to do it while dry.
The only thing that can go wrong is if you forget who you're cutting it for. I'm guessing you have a head to put it on while you cut? Wig heads are generally smaller than a human head. If you forget that and you cut it to fit the head, then everything is going to be too short on you.
Put the wig on first and measure what you need to cut and how long. You can even mark it on the fibres with a felt tip, just lower than what you need so you can remember where to cut.

Thanks a lot - I was struggling to mark cutting points on my other wigs with clips etc; I never even thought of using a marker pen. Yup, I'm using a wig head and trying it on periodically to make sure it's okay. That was really helpful!

Good advice on trying on the wig periodically - my head is about a million times bigger than the standard wig head. Anything that looks long on the wig head looks short on mine! XD;;;

Anyway, before you chop your wig too much, check that it's thick enough. I'm not familiar with that wig seller so I've no idea what sort of quality the wig is, but generally if you cut wig hair shorter, there's a much higher chance that you'll expose the netting underneath! So make sure you have a wig with thick hair before you start reducing the lenght. If what you have is too thin, it might be better to save it for something else and getting another one that has thick hair.