Leave husks on until you are ready to eat.
If you’re going to use within 4-5 days, you can simply leave them on your countertop.
Tomatillos can be kept in the fridge for 2-3 weeks, as long as they are stored loosely in an unsealed paper (NOT plastic) bag. This helps control moisture, and therefore, freshness.
To help remove husks, you can soften by placing in a bowl of warm water- this will help move the husk away from the fruit. Wipe fruit with a damp cloth, if desired, to remove stickiness.