When you want to quote someone else's text go to their post and click on "Quote" in the upper right corner. That will open a new box for you to type your comments and their comments will be in box below yours. If you want to delete some of the content just highlight what don't want and hit enter and it will disappear. Or leave it as it and it will quote ALL of the person's post.
To see if you did it right click on the "preview post" button and it will show you what your post will look like. If you like it...then click on Post and you are done!!
When you want to quote more than one post or break the quotes into different areas, forget the above directions. Actually, I never use that method anyway, because the alternative is easier and allow me to place my quotes anywhere I want them in my post.
Cut and paste the part you want to quote into your post exactly where you want it. Highlight it, click on the "QUOTE" button above the text box. Everything highlighted will be in a quote box in your post. It will not tell who said it, as WreckWench's method will, but that's easy to add. Before the quoted text, you'll see [] with QUOTE inside. To add the name, simply type "=WreckWench" between "QUOTE" and "]." It will now give WreckWench credit for her words.
You can also preview your post to make sure you did it correctly by following the preview instructions WW gave us above.