Being right handed, but raised by a left handed mother, I was already screwed up about directions before SR and SL even came into it! I learned a trick drilling with the marching band in high school. If you're in a situation where directions are and issue, squeeze your left fist tightly as a physical reminder of "left."
Of course, I right "SR" and "SL" really big on the upper interior corners of my script binders, so I don't have to think!