Best method for cutting out background?

[enginestar]

I've been through tutorials on youtube...

Using Lasoo is OK for some parts. Not all.

Using layer mask + brush is OK... but edges are hit and miss - some OK, some not.

Is there a layer mask version of the Lasoo tool?
The thing is, once a part is deleted, I can't get it back.

Or... are there any other better methods?

Thanks.