Need a complete/detailed tutorial on KEYING

Hello there,
Does anybody know any good tutorial about Keying with FCPX? 
All I found on Youtube couldn't help me at all. 

Thanks!

Edit: I did found some good tutorials, but I'm actually struggling to get rid of the green light 'strokes/edges' on the talent. I've tweaked in lots of ways all resources available - and I couldn't - so far - get a nice result. I mean, I can get rid of the strokes on the character (talent), but it always has 'collateral effects' - it messes up the hair, etc.

What you're trying to do is done during the shoot. Back light the talent, make sure they're far enough away from the green screen to not get the green light reflecting in their halo. Yes, if you get too much green light on the talent, it can be very difficult, if not impossible to correct.

Hi, Ben.
I've just got the footage from a client, it wasn't recorded by me.
I actually can manage to 'disguise' these edges on the talent, with graphic elements/lights/gradients and so on (I'm not trying to fake real scenarios, it is admittedly virtual, which helps on this case).
Even though, I'm missing a better tutorial with real examples with bad green screen shooting. Perhaps a FCXP course..i don't know.

support.apple.com/guide/final-cut-pro/us...03bc/10.6/mac/11.5.1
Look through the Advance Key Tools section of that page.
Spill and Light Wrap are the tools you need.

Ripple has this tutorial, also.
www.rippletraining.com/blog/final-cut-pr...-in-final-cut-pro-x/

Hi, Ben. 
I've watched the tutorial you sent, pretty cool, it helped a lot.

I'd like your opinion on the footage I'm talking about. It is attached here. 
What would you say to the person that recorded it? What guidelines would apply here?

Thanks!

I'm not sure just looking at one show with the hair blurred out. If you want to share the clip with me, I can see what I can do. benb at bbalser dot com