Create Add Remove Edit Labels

Create New Label:
Here I am going to apply label ‘test’ (Add Label) and then delete label ‘test’ (Remove Label)  from multiple posts.  First to apply the label, I’ve to create label ‘test’ (New Label), to at least one post. 

1. select the checkbox for the post,
2. use the dropdown menu,
3. select ‘New Label’,
4. type the name ‘test’ and OK.

Add Label to multiple posts:

Here is where the ‘toggle’ function of the label menu plays its hand.  And to be frank, I spent around 20 minutes scratching my head (to be polite).  That’s why I’m spending another 30 minutes to write this one up - so someone else doesn’t have to waste 20 minutes. :-)

1. select the checkboxes for 2 (or more) posts,
2. use the dropdown menu,
3. scroll down to the required label ‘test’; popup says you can ‘Add or Remove Label Test’,
4. click and the label test is applied to the selected posts.

Remove Label from multiple posts:

This is the same as the earlier step.

1. select the checkboxes for 2 (or more) posts - 3 here,
2. use the dropdown menu,
3. scroll down to the required label ‘test’; popup informs you can ‘Add or Remove Label Test’,
4. click and the label test is removed from the selected posts.

Add or Remove Label from individual posts:
Just joking…

Edit a Label:

Suppose you want to modify an existing label - say modify ‘test’ into ‘tests’.  The easiest option is to select all the posts labelled ‘test’, Create a New Label ‘tests’,  apply to all those posts and then remove the old label ‘test’. [Tip:  Add the new label and *then* remove the old label - don’t try it other way around]
:-D
Cheers!

from http://www.madmadrasi.net/2012/09/add-edit-or-remove-labels-in-multiple.html