Not the most pleasant job in the world, but necessary. Some dogs have very deep set anal glands that you cannot get to yourself. If you have a grooming parlour anywhere near, they will probably do it for you (for a fee!).
Now before the rest of you start to panic, most dogs will never need this doing, but some dogs need it doing regularly. Feeding a dry complete food, or bones will help as the firm poos help push to nasty stuff out naturally.
All those of you who say you will never feed bones might like to think again!