I assume that someone has told you it is the Carbon Brushes that need replacement???... If so they are normally the electrical contacts in the electric motor that drives the drum. Conventionally, the motor is connected to the drum via a drive-belt, just like the fan belt in your car. You will need to loosen the belt in order to remove the electic motor. The carbon brushes are located where the wiring 'plugs' into the electric motor. Obviously they are removable and are normally spring loaded. Do a search on line for your machine's electric motor brushes so that you are familiar with what they look like. If you can use a screwdriver and spanners, this job is straightforward albeit a bit messy.
Barry
November 2010