To make sure you get that awesome grade, you need to give yourself some extra time to revise your paper. Yes, you can (and should) run a spelling and grammar check, but you also need to read your paper and edit for spelling, grammar, and clarity yourself. (Spell check with caution! Sometimes the spell check will mark correctly spelled words as errors and vice versa. The same goes for grammar. Grammar check is a good place to start, but you need to finish the revision process with your own brain.) I recommend a two-step approach to revising papers—Macro and Micro Revising.
Macro Revising
First, you should read through your paper to make sure it makes sense. Is it organized well? Are the arguments placed in a logical order? At this point you’re looking at the big picture and revising your paper for its organization. You can also ask a friend or roommate to read your paper for its overall clarity.
Micro Revising
Next, you should read through your paper to edit any sentence-level mistakes and misspellings. Is the sentence a complete sentence? Is the sentence punctuated correctly? Are the words spelled correctly? At this point, you’re checking your paper for any grammar and spelling mistakes. Also, you can focus on the verbs—the action. Work on replacing weak verbs with strong verbs. (“The party featured a live band” is stronger than “The party had a live band.”)