Today I'm gonna give the tips on how to change the label name of your posts. Let's say you have a bunch of posts with the label name 'My Blog' (label name is taken from my blog) but you've decided that you'd rather call it 'My Diary' instead. You can edit the name of a label directly from each post (as I did before I found the trick - it took me a long time to change only one label), but there's a simple workaround to accomplish your goal:
1. Go to the Posting --> Edit Posts tab for your blog.
2. Click My Blog in the label list.
3. Click Select: All to select every post with this label (see picture 2).
4. From the Label Actions... menu, choose Apply label --> New Label...
5. Enter My Diary as your new label. (If you already have some posts with this label, you can simply add that label, without creating a new one).
6. Now all the selected posts should have both labels My Blog and My Diary (picture 5). From the Label Actions... menu again, select Remove label --> My Blog, and you've completed the switch.
That's all. If you have a large number of posts with this label, they may not all appear on one page. You can show more posts at once using the Posts Per Page menu. If you still can't show them all at once, then simply repeat the steps above until you've changed the labels on all the posts you wanted to affect.