
Okay. :) First off, make sure that both the bitch and the dog have passed their relevant health testing with good results. You can find a list of what is needed for each breed here:
http://www.thekennelclub.org.uk/download/1100/abshealthreqs.pdfand by typing in the stud dog's registered name you can find out if he has been tested, what for, with what results and when, here:
http://www.the-kennel-club.org.uk/services/public/health/search/You'd also be well adviced to ensure both the bitch and dog have been shown or worked or assessed by a few people in the breed, ensuring they are good examples of their breed -even the poorest quality dog can have Champions in their pedigree so that in itself does not mean all that much, unless one of them is a Champion themselves.
Secondly, buy "The book of the bitch" it can be found in many petshops and also on
http://www.amazon.co.uk It's invaluable for advice.
Thirdly, make sure you have buyers already WAITING. It's not a good time to breed at the moment as people aren't buying pets during the credit crunch, even many top breeders are left with pups, and so you need to have a waiting list of several people before you mate the bitch to ensure you don't get left with an entire litter -assuming it isn't one of the tiniest toybreeds which only have one or two pups.
Then of course you both need to make sure you have all the equipment needed, have a chunk of money saved in case of big vet bills (I try to always have £1000 available at least) and one of you is able to stay at home with the pups for several weeks. And start saving newspapers straight away as you will need loads.
As far as the actual mating goes, you need to observe the bitch. Some are ready on day 3, some on day 23 -with everything in between. It's no good just visiting the stud dog on any given day, the bitch must give out the right signals showing she is ready to be mated. This normally means she will "flag" her tail (moving it to one side) and stand still waiting for the dog. Presumably she's had a few seasons already so your girlfriend should be able to recognise the behaviour.