The best solution is a good defense. If possible, store items in an enclosed airtight container with a desiccant. A desiccant is material that absorbs moisture out of the air. Desiccants are commonly found in small packets packed with items that can be damaged by moisture such as cameras, electronic gear and vitamins. The most common desiccants are silica gel crystals.
Some desiccants turn color when saturated with moisture.
Tools that are too large to store conveniently are best protected by a clean wipe with moisture displacing rust preventative. At the Darex manufacturing plant we use Rust-Lick brand to protect our tools from rust. The best way to produce proper relief or clearance is to use a quality made drill-sharpening machine. This advice may sound rather self-serving, but the accuracy and consistency of a good sharpening machine will out perform the most experienced machinist's hand held sharpening job. The complicated geometry opens up many possibilities for errors.