Turn the breadmaker on its side and wipe off the crumbs with a brush. Don't wash the interior with water. This will damage the electric components. Use the brush to sweep flour residue as well. If there's liquid inside the unit, use a clean microfibre cloth to wipe it.
Use a moist cloth to wipe the heating elements clean gently. Never spray these with water as it could short some electrical elements out.
Clean the bread pan by wiping off crumbs and other dirt. Then, wash it with a warm soapy sponge and rinse it with clean water. Gently scrub off the surface using a non-abrasive sponge, especially if the pan has a non-stick coating. Let everything dry before you put back the bread pan in the machine.
Cleaning your breadmaker after each use will also help prolong its lifespan and avoid burnt loaves and caked-on grime.