Use a flea comb outside, and keep a container of soapy water nearby for drowning the fleas, or comb your pet in a bathtub where you can rinse the fleas down the drain. Start by running the comb gently through your pet's coat. After each run through, dunk the comb in the water and leave any fur caught in the comb in the water. The soapy water will kill the fleas. Continue this procedure until the entire pet has been combed, making sure to comb their underside. A flea comb can be used every day when fleas are bad, and can help prevent fleas entering the house if used before the pet comes inside.