Request that a teacher, professor or another qualified professional take a look at your work. Ask them to mark mistakes you've made in your writing. This will save you a lot of time when you go to correct the grammatical errors. Otherwise, you will have to look for errors yourself.
Start by highlighting or circling all the punctuation marks. This should include periods, commas, colons, quotation marks, apostrophes, hyphens, parenthesis and any other punctuation marks used. Look under each section of your style guide to read the rules for each punctuation mark. If you have incorrectly used a mark, make the corrections needed. Some common mistakes made with punctuation marks are incorrectly using comas and quotation marks together, leaving out commas and using colons and semi colons incorrectly.
Highlight all the abbreviations in your writing. Use a different colored highlighter than the color you used to correct your punctuation marks. Turn to the section about abbreviations in your style guide. Make corrections where necessary. Use your style guide when in doubt.
Highlight all the titles you can find. Examples of titles include books, movies, songs, speeches, works of art. Places and seasons are also considered to be categorized under the "Titles" section. People commonly forget to capitalize or incorrectly use quotation marks when they aren't supposed to. Use your style guide to make corrections where necessary.
Rewrite your paper after you have completed correcting all errors. This should be your final product. Congratulations on correcting your own grammatical errors. You have become familiar with many of the style guide rules. This means your writing should have fewer mistakes the next time you write.