The whole splitter, I started at the left hand side and pulled outwards.
How far round are you guys starting from? I'm starting from the first big bit I can get a grip on and pulling forward (The way the car travels)
Should I start from the wing and pull sideways?
 
I started right from the end of the splitter just in front of the wheel arch, yes. You might want to either get a good, substantial pair of pliers to get a grip on the plastic, think that's how I got it free to start with, either that or if you want to use your hands then a pair of thick gardening gloves should stop it digging in to your hands so uncomfortably.