Get in the right mindset before you even start reading. Read the text with an awareness of how it makes you feel. Don't passively read your text. Instead, engage the text and ask questions.
Takes notes while reading the text. This can be underlining or highlighting notable words and phrases, or asking and answering questions about the text. You may find it helpful to ask questions like, "How does this passage make me feel?" or "What do I think should happen next?" as you read along.
Do a free-write response to the text. Just write your reactions and don't worry about proper grammar. The point of this free write is to find out how you would like to focus your final paper. Essentially, you're trying to find the argument you're going to make with your paper.
Write an outline with your focus in mind. Your paper should have an introduction, body and conclusion like any paper. When outlining, keep in mind that you want to guide your reader how you came to your final reaction. You'll need to quote the text in your paper, so you may find it helpful to figure out where you'd like these quotations to go in the outlining stage.
Write your first draft. Use your outline as a guide, and remember, you probably will have to stray from your outline some. Your outline is just a guide. You don't have to follow it exactly.
Proofread and edit your draft. Check for grammatical errors and misspellings. Make sure you lay your essay out in the best possible order. You can often rewrite or rearrange paragraphs and sentences for more impact or clarity. In a reaction analysis paper, you'll likely be working in a linear fashion, taking the reader from the beginning to end of a text.