The first rule is simple: don’t copy content from other blogs. It is unethical and Google penalizes duplicate content. Although it will not ban your site from its results forever, Google will send the guilty entry to the supplemental results. Once you are there, it is difficult to come out. The whole purpose of SEO is to optimize a site to rank naturally in the organic search engine results for relevant terms and relevant content.
So please don’t copy! You should create your own unique content. I’m talking about original articles written by yourself. Of course you can grab some ideas from other sites, but make sure you don’t copy-paste the articles or you will be in trouble and your site will get penalized by most search engines.
For example, there are many similar titles in the search results: Top 10 SEO Tips, Top 10 SEO ideas, etc. So Google shows less than half of these content pages in its results, because it is trying to avoid duplicate pages. So no matter how cool these Top 10 or Top 100 titles are, try to avoid them. Come on, it shouldn’t be so difficult to come up with a nice, unique title created by yourself!