Fakie is basically in your normal stance but going backwards. You should be rolling backwards with your feet where they normally are. This is called fakie because if you pull off an ollie while rolling like this, you could probably get away with telling people it was a nollie. It is good to learn tricks like the kickflip rolling fakie before rolling forwards normally, this is because it is easier to keep the board under control. Also there isn't that temptation to go really fast, because it's a lot harder.