Just rock up and go with it, jiu jitsu is a weird thing. You pay money to get beaten up by other people, when they start to strugle to beat you you start to give them tips on how they can improve to beat you, the more they beat you the better friends you become. Best thing you can do is turn up, i have many friends who say they are gona get fit first befor they start, wich meens they usually never turn up. Also Popovitch is in Florida, i realy like his jitz.