If I were you, I wouldn't try that on my car.The clutch is there to be pressed while shifting. So, better use it while it is there. If you really wanna try. Get rolling in the first gear. Slide the gear to nuetral and let your car get in a stable state (i.e. neither accelerating nor deaccelarating). At really low RPM (around 1500 to 2000) put the gear in second. If you hear a grindddddd, oops, you did it wrong... And if you try this a couple of more times, you are looking at the invitation to funeral of your transmission system.