It’s an instinct for your dog to want to investigate things you put near his muzzle, so he is likely to touch the bell lightly with his nose. Be ready for that moment and click and treat. If he is apprehensive, put the treat very near the ribbon of bells so that he almost HAS to touch them in order to get at his treat.  When he touches, click and treat!
^ Herron, Meghan E.; Shofer, Frances S.; Reisner, Ilana R. (2009). "Survey of the use and outcome of confrontational and non-confrontational training methods in client-owned dogs showing undesired behaviors" (PDF). Applied Animal Behaviour Science. 117 (1–2): 47–54. doi:10.1016/j.applanim.2008.12.011. ISSN 0168-1591. Archived from the original (PDF) on October 29, 2012.

Most puppies have to eliminate about every 30-45 minutes except, of course, when sleeping. Their elimination schedule will depend upon when they last ate or drank water; rambunctious physical activity; and the big unknown - personal preference! That's right - every pup has their own inherent elimination schedule. The good news is, puppies sleep alot!

Though it differs by each individual dog this is the time when most will come up with their own little way of letting you know they’ve got to go. It might be crying at your feet, ringing a bell you’ve set up or waiting at the door — just be sure to pay attention to these signals & follow up. Once your dog knows how to get your attention when he’s got to go you can relax a little and congratulate yourself on a job well done.
Non-associative learning is a change in a response to a stimulus that does not involve associating the presented stimulus with another stimulus or event such as reward or punishment.[48] Habituation is non-associative learning. An example is where a dog that reacts excitedly to a door bell is subjected to repeated ringing without accompanying visitors, and stops reacting to the meaningless stimuli. It becomes habituated to the noise.[49] On the other side of habituation is sensitization. Some dogs' reactions to the stimuli become stronger instead of them habituating to the repeated stimuli or event.[50] Desensitization is the process of pairing positive experiences with an object, person, or situation that causes fear or anxiety.[51] Consistent exposure to the feared object in conjunction with rewards allows the animal to become less stressed, thereby becoming desensitized in the process. This type of training can be effective for dogs who are fearful of fireworks.[52]

Taxi your pup for about one month (until the pup is about 3 months old as this should give the pup enough time to develop some bladder and bowel control). By doing so, you will prevent many mistakes. At the same time you will train a stong preference in your pup to eliminate in your chosen spot. The pup will also learn that being picked up gets - kisses !

Konrad Lorenz, an Austrian scientist who is regarded as developing the foundations of ethological research,[16] further popularised animal behaviorism with his books, Man Meets Dog and King Solomon's Ring.[17] Lorenz stated that there were three essential commands to teach a dog: "lie down" (stay where you are), "basket" (go over there) and "heel" (come with me).[18]
A dog learns from interactions it has with its environment.[1] This can be through classical conditioning, where it forms an association between two stimuli; non-associative learning, where its behavior is modified through habituation or sensitisation; and operant conditioning, where it forms an association between an antecedent and its consequence.[2]