Can anybody tell me how you chose the ''pick of the litter'' I know it may be different for individual breeds and you learn which pup will make the best dog through experience, but what simple factors should I be looking for when doing this. Can you tell much when the puppies are so young, do you feel that some dogs may grow into something you have not predicted. Please can you advise me on what I should be looking for.

it really depends on what you are looking for.
Are you talking in terms of breed standard for showing or temperament??????

It is at best an educated guess and matter of Opinion. with some litters you could invite a half dozen people experienced weith puppies of your breed and each would choose a diferent one.

Now that I have bred several generations I find I look back at Photos of the sogs I have as puppies, and compare their traits then and now, and this helps with current pups, but it is still guess work and luck. some really promising pus just go wrong and don't defvelop as expected, and some Ugly ducklings turn into swans.

More often than not breedewrs get pictures or vistits from dogs they have bred wiothsing they were in the ring, rather than their littermates.

depends entirely on what you want the dog for! if you want a show dog then you clearly need to consider breed type along with basic conformation & identify any faults depending on your breed. If you want it to work then as well as type you also want to consider the working instincs of individuals in a litter.....when i picked my last working long dog I watched to see which one was leaping the barrier in the pen 1st!
If you want a pet only, then you may consider picking one that has a more placid temperament that suits your household rather than the dominant "in your face " puppy .....all depends on why you want that particular dog in the 1st place & if you give more information then maybe we can help some more!