What are the rules for a false start on an offensive lineman?

I play o-line and don't exactly understand the rule for false start. Can you not move at all? Or can you just not move your hand?What are the rules for a false start on an offensive lineman?
Once you enter a ';set'; position, you cannot move at all until the ball is snapped. If you do, you have started before the play, hence the term false start, and will be penalized 5 yards.





A set position is when you have clearly entered your down position and haven't moved for a full second.What are the rules for a false start on an offensive lineman?
For a false start you can not move at all. If you jerk twitch or even wiggle you risk being called. The only time you can move is when you shift and that is only before the quarterback says ';set';. Once he says set if you move you might be called for false start no matter what you move.
It is scientifically, biologically impossible not to move at all. I guess there is some tolerance for what a reasonable defensive lineman would conclude that enough movement to show that you think the ball has been snapped.
They can't move before the ball is snapped
Once your set you cannot even flinch slightly
after you've been in your ';set'; position for one second, not at all