This tutorial presumes you have MetaMask installed already in Chrome.
Let’s get started and get that 18.75 of test ether into your Rinkeby Test Net MetaMask account.
First, navigate to the faucet.rinkeby.io.
Second, copy your public address from MetaMask.
Third, post your public address somewhere on Google Plus, Twitter, or Facebook. It does not matter what surrounding text you include. The faucet will parse the public address automatically.
Fourth, past the link to the post in the Rinkeby Authentication Faucet.
Fifth, select 18.75 ether to receive from the Rinkeby Authentication Faucet.
Sixth, wait for the transaction to be approved and processed.
Seventh, check your Rinkeby Test Net account in MetaMask to see all the ether you just got.