Hey Everyone, just to let you know how it all went! In the end I tried a lot of different techniques and all seems to work really well, which suggests to me two key things.
1) I need to make sure not only are my nails super short (they are normally short, but not super!!) but also that I file away any hard skin on the edges (I play guitar a lot so it can be a little rough)
2) Moisture, as my OH's sex drive is pretty much non-existent (I used try it on with her constantly until a week later she gives in, but I'm trying a different tactic now) I realise I need to work her up to being ready first and the lube helps lots!
In some ways I'm glad it wasn't my technique, although I did find out some new things that make it more interesting for both of us.
By the end she was screeming for me to fuck her, and although I really wanted to I never gave in, not sure if she orgasmed there was a lot of internal contrations and body movements, but she definetly enjoyed herself.
Thanks again everyone!!!! If ever we meet I will buy each of you a drink!