Brush the sofa using a rubber-bristled brush. This loosens stubborn dog hairs.
Sprinkle baking soda over your couch before vacuuming. Baking soda reduces the static charge of pet hairs, making them easier to remove. Baking soda also neutralizes pet odors. Spraying diluted fabric softener on the couch before vacuuming has a similar effect.
Vacuum the couch using a hose or brush attachment.
Dampen your fingers. Rub your fingers along the sofa. The dog hair clumps to your fingers. Allow your sofa to dry. Similarly, you can wear a rubber glove and dampen the tips of the fingers.
Roll a strip of duct tape around your hand, sticky side out. Pat down the sofa. The stickiness of the tape acts like a lint roller, picking up any remaining hairs. While sticky lint rollers are readily available commercially, using them on a regular basis for furniture can be cost prohibitive.
Brush your sofa with a dog brush. Dog brushes are designed to remove fur. Test an inconspicuous spot on your couch first to make sure the brush doesn't damage the upholstery.