Sew at a slow, steady pace. Trying to move too fast, and rush things, could end in a trip to the first aid kit.
To be on the safe side, unplug the sewing machine before threading the needle. If unplugging every time you want to thread the needle seems too inconvenient, at least turn the machine off. Even if you’re sure the machine is off, make sure your feet aren’t anywhere near the pedal.