Helpful hints for Writing a Critical Response Paper:
See page discussing MLA Format (i.e. using proper header, etc. )
See page listing more specific hints for the Research Paper 

First and foremost, remember that this is a Critical response paper, NOT a Personal response paper.
You must maintain an academic perspective throughout your paper. You are presenting an argument and supporting it with evidence from the text or other sources.  Therefore, AVOID the following types of statements: "It seems to me," "I think," "I believe," and "It is obvious that." In fact, avoid using the first person (and second person, for that matter) altogether.

It must contain a strong thesis statement in a strong introductory paragraph.
Be sure your first paragraph is an overview of the contents of your essay. It's almost like an outline for your reader that is written in complete sentences. Sometimes it's helpful to go back and refocus your first paragraph after you've finished your essay.

The body of the essay should be filled with information related to your thesis.
Each paragraph has a topic sentence and a concluding sentence.  You should use evidence within your paragraphs which further explains what your topic sentence introduced.  Don't forget to clearly express your own opinions. Avoid repeating yourself. Use past tense to discuss historical or biographical events, but present tense when discussing literature.
Each time your read a text, the events "occur" all over again. Therefore, as you describe these events, always use present verb tense:  "Victor creates a creature out of dead body parts."  "The other mariners appear to come back to life after they have been dead for a while."

Evidence is needed in your paper.
Be sure to "back up" all your points with either examples from the text, citations from the text or your outside resources.
Using proper MLA format, include parenthetical citations with proper punctuation and a Works Cited page.

Grammar, spelling, and punctuation are critical to your reader.
Good grammar will make your ideas clearer to your reader. Proofread your paper. Check for spelling errors. USE SPELL-CHECK !
Do not use run-on sentences. Again, it's better to make shorter clearer sentences than long confusing ones.
Commas are often needed when you do write a longer sentence (but don't overuse them!).
Try to use smooth transitions between one paragraph and the next.

A strong conclusion leaves your reader fulfilled and your paper complete.
Briefly sum up your thesis. Perhaps your final thesis has a little more content than the thesis in your introductory paragraph because the reader now knows where you are coming from.
Don't be afraid to make your final paragraph REALLY COUNT in some way. Again, it gives the reader something to remember you by.