How to play on multiplayer on minecraft?

I bought my minecraft and i went to play multiplayer and it says no connection please someone help me

Added (1). for a mac

Matthew

Make sure you go to Windows Firewall and enable it's rule. Second, go to properties, if its blocked, unblock it. If you have premium, enter you're email and password. If it's cracked, do the same. Make sure you're Minecraft is updated to cracked and premium to 1.7.4 or 1.7.2. If you have premium, make sure you download their launcher from Minecraft website. [EDIT] Oh, mac? Sorry, can't help you. Try Google.

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