To enable Bluetooth on Android, go to Settings > Wireless and Networks and from there turn on Bluetooth.
Now you are able to adjust its settings:
Device Name is the name shown to other devices in order to start data sharing.
To make other Bluetooth devices find your phone or tablet, you will have to enable the Visible option which is turned off as default for security reasons.
Visible Time Out is the amount of time you specify the device should be visible to others after which it automatically make the device name invisible.
On some Launchers like TouchWiz for Samsung Galaxy phones, you can easily tap and drag down the menu on the up side of the screen, and easily select the Bluetooth icon