Firstly, don't clip the top third of his ears! It is American Cocker Spaniels that have the top third of their ears clipped short.

On an English cocker you want to achieve an indent at the top of the ears/head, I do this with thinning scissors.
On the top of the head I use a combinations of handstripping and stripping knife. However to make it easier use thinning scissors, I've just started to do this when I'm short of time and have got good results. I wouldn't clip the top at all.
Barney is 17 months and I've only just started to clip his face and I take very little off now. Up until the last couple of months I would just handstrip any bits that needed doing. You don't want to clip it very short, that is how you do an American cocker.
I use a coat king on his back, I've never clipped that so can't advise on that.
I use thinning knife on the front of his legs, thinning scissors could also be used. His feet should look like "cat paws" and you can do this with thinning scissors. Between his pads underneath you can either clip them out or do with small scissors.
You could use the clippers to clip from the breast bone up, throat and under the chin, also the neck under the ears.