Typically, most people take months making the decision and then are forced into a situation where they have a matter of days or a week at best to act on that decision. This time crunch can mean the difference between life and death to your dog. Sometimes there are no other options than the shelter. Get your dog spayed or neutered. Also update, if necessary, your dog's vaccinations and keep records handy.
Ethical breeders feel responsible for every puppy, each life they have had a hand in creating.
Good breeders often have waiting lists of people wanting a puppy who might consider adopting an adult dog. Assess your dog. Take some time to write out a list of good and bad points about your dog. This will help you develop an honest evaluation of your own dog. Tell any interested party everything about your dog.