Don’t underestimate these less popular keywords. Long tail keywords with lower search volume often convert better, because searchers are more specific and intentional in their searches. For example, a person searching for "shoes" is probably just browsing. On the other hand, someone searching for "best price red womens size 7 running shoe" practically has their wallet out!
While that theory is sound (when focused on a single page, when the intent is to deliver utility content to a Google user) using old school SEO techniques on especially a large site spread out across many pages seems to amplify site quality problems, after recent algorithm changes, and so this type of optimisation without keeping an eye on overall site quality is self-defeating in the long run.
Submit website to directories (limited use). Professional search marketers don’t submit the URL to the major search engines, but it’s possible to do so. A better and faster way is to get links back to your site naturally. Links get your site indexed by the search engines. However, you should submit your URL to directories such as Yahoo! (paid), Business.com (paid) and DMOZ (free). Some may choose to include AdSense (google.com/adsense) scripts on a new site to get their Google Media bot to visit. It will likely get your pages indexed quickly.
The higher the search volume for a given keyword or keyword phrase, the more work is typically required to achieve higher rankings. This is often referred to as keyword difficulty and occasionally incorporates SERP features; for example, if many SERP features (like featured snippets, knowledge graph, carousels, etc) are clogging up a keyword’s result page, difficulty will increase. Big brands often take up the top 10 results for high-volume keywords, so if you’re just starting out on the web and going after the same keywords, the uphill battle for ranking can take years of effort.
Google is all about ‘user experience’ and ‘visitor satisfaction’ in 2019 so it’s worth remembering that usability studies have shown that a good page title length is about seven or eight words long and fewer than 64 total characters. Longer titles are less scan-able in bookmark lists, and might not display correctly in many browsers (and of course probably will be truncated in SERPs).
So: how to proceed? On the one hand, SEO best practices recommend that you include relevant keywords in a number of high-attention areas on your site, everywhere from the titles and body text of your pages to your URLs to your meta tags to your image file names. On the other hand, successfully optimized websites tend to have thousands or even millions of keywords. You can't very well craft a single, unique page for every one of your keywords; at the same time, you can't try to cram everything onto a handful of pages with keyword stuffing and expect to rank for every individual keyword. It just doesn't work that way.
Understanding the balance of terms that might be a little more difficult due to competition, versus those terms that are a little more realistic, will help you maintain a similar balance that the mix of long-tail and head terms allows. Remember, the goal is to end up with a list of keywords that provide some quick wins but also helps you make progress toward bigger, more challenging SEO goals.
You’ll likely compile a lot of keywords. How do you know which to tackle first? It could be a good idea to prioritize high-volume keywords that your competitors are not currently ranking for. On the flip side, you could also see which keywords from your list your competitors are already ranking for and prioritize those. The former is great when you want to take advantage of your competitors’ missed opportunities, while the latter is an aggressive strategy that sets you up to compete for keywords your competitors are already performing well for.