Bluetooth devices can sometimes wake your Mac from sleep mode even when you're not around. Here's how you can put a stop to that so your Mac stays in sleep mode.
1. Go to System Preferences.
2. Go to Bluetooth.
3. Click on Advanced.
4. Uncheck the "Allow Bluetooth devices to wake this computer" option.
5. Click the OK button.
According to OS X Daily:
Many Mac users choose to put their computers to sleep when they’re not in use, and unless Macs are scheduled to wake at a specific time, the computer should stay asleep until it has been manually awoken by user input, like a key press or mouse click. Should of course is the operative word here, because some users have discovered that their Macs are waking from sleep seemingly at random, with no obvious reason for this to happen.More at OS X Daily
Additional resources for OS X
This article is published as part of the IDG Contributor Network. Want to Join?