Adding FB, Twitter options to a WP theme

I'd like to add some SNS buttons to my WP page. Would this be done manually via html or would this be done via WP plugin? Can you place WP plugins anywhere you want?

For example:


I'd like to put them at the top right or bottom right of this home page and maybe on all pages (I guess it would then be a footer then?).
http://livedemo00.template-help.com/wordpress_40640/

I'm buying this WP theme because I'm not a designer and it's all ready to go. I'd just like to add the buttons and obviously use my own logo and media. Also this theme is responsive which is the main reason I'm updating my site.

BONUS question: Regarding the design of the WP theme above; What do you think of the menu being in the middle instead of the top? Not an issue? neither here nor there?




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