1 Seal the moisture: To protect the wooden cupboards, desk drawers, etc put camphor in your cupboards; it takes away the moisture and protects your clothes. Neem leaves are effective against silver fish.
2 Goodbye termites: These are a major problem wherever there is water leakage or high humidity. They would require professionals to do a really complete job. Check the house for any signs of termite infestation during the rainy season.
3 Hardwood wise: Make sure hardwood floors are free from moisture. Wax them to protect them, as the moisture content in hardwood floors tends to make them warp.
4 Carpet care: Carpets, especially wall-to-wall carpets, need to be vacuumed regularly with cleaners. A good carpet cleaner will also keep them from smelling musty. Rugs should be rolled up during the rainy season. If you wrap them properly in polyethylene sheets, they will be safe from both water damage and insect infestation.
(with inputs from Pure Home and Living)