This question already has an answer here:
I finished deploying(compiled and migrated) my contract to Rinkeby test network. So, now I'm trying to go to MetaMask and clicked on Rinkeby TestNet and don't know what to do after. How do I get my Rinkeby's private key or json file to import to metamask? All I can see is ["account Address", "account Address", "account Address"] when I put "eth.accounts" on my geth console.