There are many hints on how to get yourself noticed above the babble of authors, but few rarely deliver. I guarantee you that each one of these will work. Sort of.
1. Assassinate a major head of state. This will take some planning and the downside is that you'll spend a minimum of 20 years in jail, probably the rest of your life, so this really only suits older people who have retired and whose children have grown up. On the plus side you'll have a bed each night, food provided and have plenty of time to write more books which publishers will be lining up to buy off you. Due to this your family will have a large inheritance when you eventually die, and if you set up the trust properly, they'll never have to work again,while the film/TV/DVD tie ins and stage plays of your life will keep them in more than milk and cookies.
2. Go to a major sporting event, strip naked and run across the pitch. While not as drastic as the first option, this will still result in a small jail sentence, or, at best, a heavy fine and community service. It will still attract publishers as you will now have a 'platform' that can be used as a marketing tool. On the negative side your children and family will get sniggered at, though not as much as you will when the replays of your naked body leaping across the pitch end up on Youtube, Twitter, Facebook and every other social media outlet. Still, you'll get media attention, be able to plug your book and have time to write more. The downside is that your fame will diminish over time unless you perform another streak within five years.
3. Go to a major news event and stand behind every reporter who's on live TV, holding your book up. The worst that can happen is you get a restraining order, but the publishers will still like the fact you've stuck out and made a name for yourself. You'll have to follow it up with blogs and tweets that point at the Youtube videos but that shouldn't be too hard for anyone media savvy enough to follow through on this. The rewards of this approach are smaller than the previous two options but have far less danger involved.
4. Spend time building up a network of people and followers. This is the slowest approach and not necessarily the most successful. It will take a few years during which you'll need to be writing a lot of things, such as books, articles, short stories and book reviews.
i) Do book reviews for major/majorish magazines and websites. I get free books from the British Fantasy Society, review them and get those reviews published on their website. It puts my name in front of the people who I hope will be buying my books at some future point, and it allows them to see my style of writing.
ii) Follow people on Twitter and post interesting tidbits. Don't just promote your book all the time as people will quickly be turned off by your approach. Share news, retweet interesting tweets, converse with authors, be part of the scene. Build up a following by following others. I was approached by an author on Twitter after giving her book 5/5 on Goodreads.
iii) Don't get in people's faces. Listen to others and join in the conversation. Most of the time you'll get ignored, but that's real life for you.
iv) Do no more than you can accommodate in your life. If you haven't got the time to promote a facebook page properly, don't have one. The same applies for twitter and blogging etc. Build it up over time and find out how you can use each tool before adopting another one.
There you have it. Four (almost) perfect ways to get noticed and have your book published. Enjoy.