Repairing a nick in leather boots can be done with products that are available for purchase at any local department store or shoe repair store. For damages that go beyond nicks, it's best to take your leather boots to a professional for repair.
Apply leather lotion to the nicked area. Use a damp rag to rub the colorless lotion on to the part of the boot that needs repair. The leather lotion will help to moisturize the damaged area as well as help to prevent further damage.
Apply shoe polish with a damp rag. The shoe polish should be the same color as the leather in the boots and should be applied on top of the leather lotion. The most effective shoe polish for repairing nicks in leather boots will come in the form of a cream. The cream will be effective in repairing deep nicks and scratches.
Buff the leather boot. Remove the shoe polish with a dry towel. Carefully buff the area of the nick to ensure that the color of the shoe polish blends in with the color of the boot.