Mirror questions.

CAn anybody tell me the ins and outs of “mirror”?
I need to have identical sides on either side of an object but can’t figure out how to get it to work
http://farm6.staticflickr.com/5031/7183338064_f32768e42e_b.jpg
Thanks in advance.
Cat

What are you trying to do? Normally you use Mirror modifier for mesh manipulation. I don’t know if you can use that Mesh Option in Tool shelve.

You probably want to use a mirror modifier over x-mirror. Here is a video that covers it.

Hi,

Also just in case, sometimes having the Topology Mirror option enabled can cause issues. Try turning it off and see if it starts working again. Unlikely but worth a try.

This is what I will need to do.
http://farm8.staticflickr.com/7098/7188420850_ee16f8c6dd_b.jpg

I do not want to have to cut both holes if the piece is symmetrical.
What would be the best way to do it?