Simply turn off your WiFi and start Ocarina of Time. Ocarina of Time 3D is an extended memory game. This means in standby with the wifi off home menu will not be running. Don't open the home menu then close the console, close the console on the games pause or save screen. Leaving the home menu open will cause it to run in standby mode which will prevent this trick from working. Currently my console has been in standby mode for four days and still has four bars. I just realized this may only work on 2DS and O3DS.