Step 1. Wash everything your pet likes to sleep on and/or spend time regularly. This includes bedding as well as rugs, the throw on the sofa, bathroom rug etc. If these objects are past the power of the washing machine (e.g. are full of accumulated dirt inside, where fleas happily reproduce), just throw them away.
Step 2. Use sprays containing insect growth regulator (IGR) (eg. methoprene or pyriproxyfen), which will prevent the larvae from developing into full-grown blood-thirsty fleas. Room foggers will not be as effective as sprays unless they contain IGR.
Step 3. Vacuum like crazy. Focus on the humid and cool spots which are not exposed to the sun, anywhere that you find dried blood and feces, upholstered furniture and crevices around baseboards and cabinets. After vacuuming, make sure that you seal the vacuum bag and put it in a covered trash container outside so that the parasites won't sneak back to your house. Also, while vacuuming, get your pet out of way to prevent the fleas that are still on your pets from jumping back to where you have just vacuumed.
Step 4. Clear you garden of fleas. Prune foliage and trim grass. In this way you will expose flea larvae to sunlight and leave them to die in pain. Move your dog's kennel, clean and clear all moist places, where fleas may find a place to nest, such as: patios, porches, sheds, stairs and dog houses. Do it all before you start applying stronger substances. When you want to use pesticides, rely on those which you can find in pet stores or at the vet's; give up on any pesticides of unknown origin.
Be particularly careful about any flea-killing treatment with Diazinon. It was banned for use in 2004, yet there are still places where you could purchase it. It is poisonous for humans so before any purchase, read the ingredient list.
Still, there is a vast array of yard anti-flea products available. They're easy to use; attach the product to your garden hose and spray all affected areas. Mind you, never spray toxic substances near flowers or vegetables! As for more natural flea repellents, try scattering slices of lemon, whose smell is a natural deterrent for fleas. There are also flea-repelling plants you could grow (eg. Fleabane Daisy Plant) but you had better consult a veterinarian first.
Step 5. To make sure you have got rid of fleas for good, apply flea control products on your pets at least once a month for the next 60 to 90 days. The flea problem should disappear - unless you keep bringing more fleas into the house, of course.