Please, I don't want to complicate my life, so, what's the best effective way to write a topic sentence for my body paragraphs?

http://www.wikihow.com/Write-an-Essay

Pay attention to #s 4 and 5. If you haven't done those things, you have no idea what you're writing for topic sentences for each paragraph.

http://www.wikihow.com/Write-a-Paragraph
Each paragraph has a topic sentence that supports the idea in your thesis statement.