The BEST tip to rank for long tail keywords is to buy them. I don't mean buy links, I mean spend to become well known be it by paying for awesome content you can't create yourself or for reputation management beyond what you can gather yourself or by offering something truly ageless and attention worthy. Longtail was sold out a while back, it belongs to the big brands now, and there is no gentle way to emphasize that.
Suggestions of the free variety - Keep building until your fingers bleed. There is power in numbers still but they'd best be solid pages each and every one of them.
- Cut down on self competition. If you have a page about a keyword or subject be sure it includes and mentions the umbrella of associated words. You don't have to keyword stuff here, that's not what I mean, but you do have to be thorough. You do NOT want 20 pages competing for the same terms being promoted at once. Pick one and let the others fall deep into archive oblivion.(note: Google is showing sites when the search term isn't even in the article so really, don't keyword stuff, but do cover your bases by having a complete article)
- Use search to your advantage. The sites that rank are but a simple search away. Read what they've written and do not settle for lesser content on your pages. You don't need weak pages constantly trying to outrank stronger ones, it's self defeating and Google uses human raters far more than they let on.
- Do NOT attempt to write an article about every keyword combo. That's not natural. If your archives read like the google keyword tool slap a picture of a cute puppy in the header and sell the site, you've done it wrong. Start over.
- The only tip you really need: Write about your passion in a way that your readers will appreciate, put them first, and search will(eventually) recognize your value.
- The tip you don't want to hear: Get social. Pick one or two social networks and interact with the people who talk about you and interact with the people who talk about what you love. If you find yourself talking about 'I love these coat hangers' when you couldn't care less you'll be hollow and the internet will ignore you. Don't be ignored. no offense to you coat hanger lovers.