One thing I tell people when they start working on cars is

1. Always check the ratchet is turning the way you want it to, before you put it on a bolt/nut.
2. Stand/lay down etc, orient yourself so that the bolt/nut would be in front of you and turn the ratchet/wrench the correct way. This will get you heading in the right directly 95% of the time. The other 5% your a dumbazz and should back away from the car after the first $100 in repairs you caused trying to fix a $10 part.