Your dogs are not human. They do not reproduce to have fun or bond with a love one. The female(bitch) is only interested in breeding when in heat all other times she could care less in such activities. During the time a young bitch is becoming sexually she may try to have a relationship with a stuffed toys. Males(dog) will do the same as the puppy becomes of age. Very young dogs may try to have relationships with other dogs, bitches, toys and may even try to have one with your leg. This is sometimes a show to who is the top dog and not so much to do with breeding.

The bitch is born with all the eggs(ovum) she will ever have. Dogs are born with testes that produce sperm until the end of his life or when he has been fixed. In breeding timing is everything. Keep records of your bitch when she is in heat.  This will also help you in knowing when her next heat will be.

Now that your bitch is in heat what's next? If you don't have a stud for breeding you should have already found one that will be the best match for your bitch. You may have to pay a stud fee or give them pick of the litter, sometimes it's both a fee and pick of litter. Make sure both are up to date on vaccines and de worming.
From the first day you bitch comes into season count 10 to 14 days and bring the stud to her. Some bitches are very clean so you may miss the first few days.  If she lets him mount her she is ready. Most bitches will not let a male mount them unless their ovum is ready. They will make a tie and that could last 5 to 30 minutes. If you don't like to wait around that long(some may even go up to one hour or so) you can give them peanut butter and that will help distract them and shorten the tie. Make sure you let them tie for 5 to 10 minutes because that's  when it all happens and after that not much will go on. If for some reason your dog has missed and ends up with a fully erect penis. Take him away and let him go back to normal size. Unlike humans which need a erect penis to mate your dog is to late if he has an erect penis. His penis need to be erect during the breeding not before the breeding. After the breeding is over place both bitch and dog in an area were they can cool off. Some breeders and 
vets say to breed again in 24 hours some may say 48 hours to make sure the breeding was a good one. Some breeder say the 2nd breeding will give you larger litters. This is not true. I have one female that I only breed one time and she has 6 to 7 puppies a litter which is a big litter for a toy dog.  It's the male that will determined the size of litter from the amount of sperm that makes their way to the eggs and the health of both dogs. So if your dog has low sperm count you can breed them 3 or 4 times and still get a small litter. I will give you info later on why your dog may have low sperm count.  Make  sure you mark down the first day of breeding.  You will have 58 to 65 days before the birth of the puppies. You should have already got everything ready before hand but if you have not it is time to get them now before the births. I will have a section on items you should have .