Optimizing long tail keywords is essential if you want to rank highly for them. You can see this myth repeated constantly all over the internet. In fact, because so few people are searching for long tail keywords in the search engines, there is little competition for them, so optimizing them is not necessary. It isn't much of a challenge to rank highly for long tail keywords. You can simply add these keywords in your content somewhere and you'll rank for them, which isn't optimization. It's as easy as that. You can get some easy traffic from these keywords, as they require no special optimization effort. An excellent example of this technique can be seen via this article about freestanding electric cookers.  Note the use of long tail words throughout this page. In one or two years this page will be easily ranked on the first page of the search engines.

Ignoring Google's guidelines will not result in your site being banned; this is simply another myth you need to be aware of when you are optimizing your site. This is mainly because the majority of webmaster guidelines offered by Google are common sense. You are not obligated to read them if you know you are not doing anything wrong. Just make sure you're not doing anything the search engines would think is direct spamming/cheating. However, it is wise to read through these guidelines every once in a while because they are always being updated and it will help increase your knowledge.

The fact that your site will be banned if you buy links to your site from other relevant websites is another myth. Google doesn't want you buying links, to be honest, and if they knew you paid for the links they would not count because they don't want you trying to artificially influence the rank of your site, but they often aren't aware of the fact. Even if they discover that these are paid links, they would simply ignore the existence of the links. It doesn't make sense for them to ban a site completely just because it advertised its link on other websites. However, when you purchase links you need to keep in mind that the same rules of link building are applicable. So whether you're buying links or not, always get links from sites that are relevant. Generally speaking, no matter how much effort you need to put into SEO, which requires quite a bit of work, it's worth every moment. The best way to learn SEO is through your own trial and error, and forget about all these fantasies that are completely false.