Keep 'em clean. Use a stiff brush and water to remove crusty dirt and wash away salt from sweaty feet.
Dry 'em right. Never dry boots in the sun, near a heater, or over a fire. In the field, you can hasten drying by taking out the insoles. At home, stuff newspaper in wet boots to absorb moisture; change the paper every 12 hours until the boots are dry.
Treat 'em well. After a thorough cleaning, or when you notice reduced water-resistance, apply the leather and waterproofing treatments recommended by the boot's manufacturer.
Stow 'em away. Store boots in a dark, dry location.
Fix 'em at once. Repair even minor sole separations immediately with Barge Cement, Freesole, or SeamGrip. Apply SeamGrip pronto to any worn stitching, separating leather, or peeling rands. Take more serious problems to a cobbler; see www.backpacker.com/repairs for a repair specialist near you.
Add extra protection. Consider applying a thin bead of SeamGrip where the sole or rand meets the leather, even on brand-new boots. You can also apply two coats of SeamGrip across the toe on boots that don't have factory-installed rubber bumpers for increased scuff and water protection.
SeamGrip (McNett, 360-671-2227; www.mcnett.com) is available at outdoors stores in a 1-ounce tube for $7. Freesole (McNett) costs $7 for 1.5 ounces. Barge Cement is available at hardware stores in a 2-ounce tube for $5 to $7.