Magic Item Attunement

Requires attunement to use magical properties
A creature can attune at most 3 items at once
- Items that come in pairs (e.g. boots, or bracers) only take one of these attunement slots
Attune by spending a short rest
- Focus only on the item
- Be in physical contact with the item
- When attuned, a creature learns how to use the item, including command words
End attunement by
- No longer satisfying a prerequisite
- Being more than 100 feet away for 24 hours
- Dying
- Another creature attunes to the item
- Voluntarily over a short rest
An item can only be attuned to one creature at a time

Dungeon Master's Guide, page 136, Dungeon Master's Guide, page 141