How do you use a respawn anchor in minecraft?

I crafted a respawn anchor, but it doesn't seem to do anything. What do I have to do to make it useful?

To make a respawn anchor usable, you must do the following:

• Go to the nether
• Place it where you want to respawn
• Use 1-4 glowstone blocks on it to give it the equivalent number of charges.
• "Use" the respawn anchor (in the same way you'd open a door)

Afterward, if you die in any dimension, the respawn anchor will use a charge to respawn you at its location.

Warning: Don't try to set your spawn point at a respawn anchor in the Overworld or The End. If you do, it will explode (similar to when you use a bed in the Nether).