If you are typing them by hand, then you can use what David(@thang) gave you.
If you are doing open graph tags, then one of the tags that FB requires is the URL (different per page).
I find it much easier just to type them in and edit then pastes the meta tags them self in the head section.
Here is the facebook Doc on the subject:
FB tends to move the Documentation around, but it should give you some samples and explain each tag property.
One great thing (if you can find it, they keep moving it) is the debugger.
Once you apply the tags to the live website enter the URL
It will give you a preview of what will be shared. Make changes and press the scrape again button.
Also here is an OG meta tag generator that seems to work ok:
http://www.metataggenerator.org/open-graph-meta-tags/
The standard: