How do these clips work? Do i just pull down or is there a certain way to do it?

if your talking about the small round clips, i just pulled them off.........no difference if they're there or not tbh lol

Yes the black round ones underneath the front bumper, pull on the bumper or the clips?

There is a small (3mm) plastic rod that pushes into the centre to spread the clip. If you push it all the way through then the clip will pull out easily, don't lose the rod though cos you'll need it to put back in.

if your talking about the small round clips, i just pulled them off.........no difference if they're there or not tbh lol

Why would they put them there in the first place??

As the guy above said. Push the middle insert until they fall out the get a flat headed screw driver under the round clip and prise them out.

The inserts usuall fall onto the undertray so be best to take that offf first

I got there in the end and done what i wanted to do but lost one of the round plastic rods, i think its in the undertray.