Yes that's it. I personally remember it by how the casings are ejected.
Most guns are made for right handers. Keeping that in mind the way the casings are ejected you'd usually want them to be ejected in a "safe" direction. Now to design something for right handers you'd want the casings ejected to the right away from you which is how the M4 works. In the case of a lefty the casings pretty much get ejected into your face.
You may laugh but when I was shooting a .22 once I almost had a hot shell eject into my face. Luckily I was wearing ballistic glasses and the worst that happened was it struck the corner of my safety glasses, and fell onto the shooting mat.
If that doesn't work for you just remember which side you put the rifle on. If it's on your left shoulder you're a lefty shooter, if it's on your right shoulder you're a right handed shooter.
It's a right handed world.....
PS: I also shoot from both sides on occasion as well (ie. when shooting around a corner or popping out on the right side of a bunker but I do tend to prefer shooting from the left side like if I'm advancing or patrolling).
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE