SirLobo93
Grammar is great. Punctuation could be machine-assisted, if needed.
Understand clauses (independent, dependent)
Understand conjunctions (coordinating conjunctions, conjunctive adverbs, etc)
Understand how a comma/semi-colon interacts with clauses and conjunctions.
Understand that there will almost always be a terminating punctuation mark (period, question mark, exclamation point, and in speeches: comma).
Anything that interrupts the sentence is set off by either commas or em-dashes (the long dash lines).
For example: I, for one, like eating chicken. The phrase "for one" is interrupting the normal sentence, "I like eating chicken." Therefore, it's set off by commas. Or em-dashes, depending on how you want to emphasize it the "for one"_ phrase.
Quotes are (almost) always in pairs. You have a starting one, and an ending one. Same for single quotes. Look for them in pairs. Read the story backward if you must.
That's pretty much it for punctuation, I think.