Take your cloth or cotton ball and dab it in some acetone, then apply acetone to the top of your super glue stain. You want it to be a thin layer, so do not soak the stain. Let sit for about 15 minutes, applying one more small layer half way through, to further release the super glue from the leather.
Take a clean, plastic knife and use the non-serrated side to begin gently scraping away the super glue, so as not to scratch the leather. If hardened pieces of glue still remain, apply more acetone and let it sit again, then repeat.
Purchase some specialized super glue remover if the acetone was not able to remove all of the glue after two or three tries. You can find this at most hardware stores, and make sure to talk to an employee about what you are trying to do, as they can help you find the best remover for your purpose. Super glue remover is much more powerful at dissolving, but it's best to try a less harsh remover first, like acetone, before going on to stronger chemicals.
Follow all instructions on your super glue remover carefully, and only apply the remover atop areas where glue remains--do not spread it around on the leather.
Apply a leather conditioner to the area 24 hours after removing the stain to help the leather keep its natural shine and avoid drying out.