Each social media site has it’s own URL and query string syntax, so you’ll need to either remember these, or just refer back to this page for them. In the following list I am using “Gearside Creative” as the page title and “http://gearsidecreative.com” as the encoded URL. Obviously, replace those with your own.
That should do it! If you have a featured thumbnail for each post, you could change the thumb variable to grab that too (I would use a conditional to say if it exists: grab it, else: use a hardcoded logo).