I had high expectations of my puppy and of my ability to train her. It was a set-back when she couldn't cope with puppy class and I bought The Gundog Club stage one training manual (sit, recall, heel on lead and a simple sighted retrieve)
Having my puppy walk on a lead, without pulling is high on my behavioural priority list. It is not on hers. I spent hours (in short bursts) and lots of treats trying to get her to walk with a loose, clip on lead.
My issue is about what behaviours to prioritise in training a lively cocker spaniel.
I now use a figure of eight slip lead to get to the fields, woods and moors and spend time playing at various retrieves while she shows me hunting. It's more fun than heel work for both of us.
As a byproduct of this she will now walk with full attention on me, more or less at heel, if I have a ball or similar in my hand.