Sleeping Bags come in 16 colors.
Pick two blocks of your favourite colored wool and one white block of wool for the cushion
and you're all set to sleep trough the night.

Sleeping bags can be placed on the ground.
Simply interact (default right click) with the Sleeping Bag to go to sleep and pass the night.

Sleeping in a Camping Craze certified Sleeping Bag will NOT set your spawnpoint.
This is intended use !
Sleeping Bags are meant to be used to safely pass the night, break up camp, and continue hiking, adventuring, discovering the world uninterrupted !

As stated before, Sleeping Bags DO NOT set your spawn point.
To set your spawn point, use a minecraft bed, or a Camping Craze Certified Tent.