I win.
"Acception" is not an actual English word, though I see why you used it. After "rules," you needed a colon, not a semicolon, as you are beginning a list. "Refrain" should not be capitalized. There is no comma needed between "slang words" and "improper grammar." Use "and" instead. "Who" should have been written as "whomever," and your general sentence structure is overall horrendous. Instead, try:
"[r]efrain from using slang and improper grammar. Any corrections should be counted with a point towards whomever made the correction; though wrong corrections should be counted against the person who made the error."
Are you feeling overwhelmed, yet?