There's nothing you can do that will automatically secure a link from me, unless you know me in real life. I won't give someone a link just so I can get one back. Some blogs in my blogroll are there because they were the first blogs to link to me, and I responded out of gratefulness to their reaching out to someone with little exposure. A few are ones I read once and loved so much that I linked them immediately. A bunch are just some of the most widely respected blogs in their categories. For a short time I linked to any high quality, contentful philosophy blog, especially if it was along my interests and not thoroughly offensive, as some are.
For many, I had enough repeat visits to the site over a long period of time and decided that the blog in question was consistently good on topics I found interesting and worth my time. A few of my favorite blogs didn't interest me at first, and then I found post after post that was just on the same wavelength as my own thinking. Some people leave comments asking for a link or asking to exchange links. Such comments will probably just get deleted as off-topic. If you consistently interact with what I write on my blog or link to my posts and discuss them in an intelligent way, then it's likely that I'll keep following you, just because I'm more likely to check your site to see what you're saying about me.
Of course, the stuff on your own site has to be of interest to me in the first place enough for me to want to read it now and then, or I'm not likely to link to you no matter how much you interact with my stuff. The most important thing is that I deem your blog good and worthy of promotion. I have very specific things that I think make a blog good. One thing I really appreciate is friendly interaction with people you disagree with and positive attempts to understand those who disagree with you. It's going to be hard to get my interest if the main purpose of your blog is to say negative things about anyone. I also have a fondness for thinking outside the box and not toeing a party line, even one I agree with. If you say things I agree with that every blogger is saying, you won't stand out as worthy of special attention. If you engage in careful analysis in a systematic and thorough way, I'm likely to be interested. If you spout off slogans that oversimplify and seem merely reactive, I'll tune out immediately. I tend to want to promote those who agree with me enough that we share a common basis but disagree enough that I will be challenged by their thinking. Regularly producing high quality stuff along these lines while consistently showing enough interest in what I do is the easiest way to secure a link from me.