Duplicate Mirror Merge -help

what ive done was to create a ferret, weasel, whatever you’d want to name it (although looks like a cat -_-) , ive done one half of the face perfect and i want the other side of its head to be the exact same. Ive tried duplicating it, mirroring the duplication and then merging it to the other side but the merge isn’t clean, it leaves bumps and stretches the lines and verticies. How can i fix this? if i select what i want an press mirror it introverts it or creates a whole nother copy of my weasel. Ive been trying to do this part for the face 3/5 hours that i’ve taken making this. Does anyone have any advice as to what else I can try? Any help would be appreciated.

http://lunafox90.deviantart.com/art/WIP-Weasel-or-Ferret-136508509 pics of my weasel if u need to see what im doing

, one ear is almost perfect and the eye is rounded out well, the other side the eye is more angular like a traingle and the ear is pointed upwards like a cats, ive tried tweaking it to look the same but i can’t seem to. I have also tried deleting that whole half of the face and then doing the duplication and merge and @@ dont wanna see that deformed head again. Also besides w and click on merge is there any other way to do it cause if i merge it goes like from ---- to ~-’

Also anyone know how to do the mirror just the one half the pic to the other, so i can do it beforehand next time i start another project?

Thank you for reading and if you reply thank you its much appreciated. (only been using blender little less than a week any insight would be helpful)

Use the mirror modifer mate:
http://wiki.blender.org/index.php/Doc:Manual/Modifiers/Mesh/Mirror

it would be great if all it did was create a mirror of what i have selected, dispite having only a few selected, its made a complete copy of my weasel, i took off the tabs xyz and it got rid of the full copy but its not allowing for copying mirroring clipping ext, i understand the concepts that were on the page, but its not allowing for what id like to do. I added a link that has a few different views of my weasel up in the original question if that’ll help at all.

Hi,

I think I see your problem.

I would personally seperate the head from the body, delete unwanted half
then apply a mirror modifier, join head and body merging the vertices back
together.

I could make the changes for you and write a little tutorial with some screen
captures as I go just post the .blend.

Reason for not attempting a mini tutorial without the .blend is I see issues with
your centre/pivot in your screenshot.

Kindest regards,

Pixeltwister