Remove the laces
Brush off loose dirt with a soft brush
Wipe the boots with a damp cloth
Mix mild soap with warm water
Dip the cloth in the soapy water and gently clean the surface
Use a suede/nubuck cleaner if the boots are suede or nubuck
Wipe away soap residue with a clean damp cloth
Stuff the boots with paper towels to help them keep their shape
Let the boots air dry naturally away from direct heat or sunlight
Brush suede or nubuck again after drying
Apply a suitable protector spray if desired
Clean the laces separately and let them dry before reinstalling