The first time I used a clicker was for agility training with William when I changed from training with a club that didn't like clickers to a trainer that did. I found it quite difficult but I guess I must have been getting it right because William made rapid improvement with his contacts.
For me, I find it difficult to click at exactly the right instant and reward immediately. If I have treats in my pocket I've missed the moment by the time I've got them out. If they're in my hand I don't have enough hands - one for holding the dog lead, one for the clicker and one for the treats = 3
So I haven't tried it with Louis yet, also because I haven't done a lot with him at all because I'm still so sleep deprived because of his poor sleeping at night
I think I'm not very nimble fingered and probably a bit slow off the mark, so please don't be put off by my problems. Loads of other people do clicker training very successfully.