There are two things of SEO techniques, i.e. on-page and off-page SEO. On-page SEO means optimizing your content or your pages on your website, so that search engine will “fall in love” with your content. And your content will be ranked higher by the search engine.
On-page SEO is very important because here you have full control over your content. You can do the optimization with maximum results. But keep in mind that your content is not only loved by search engines, but also by your visitors. Your audiences should get the maximum benefit from your content.
Conversely, off-page SEO means optimization outside your content. Here you have less control. The first thing you should do is to make your content more beneficial to your audiences. The more useful the content, the more people will link your website. Thus you will get a lot of backlinks. This is a major effort in addition to getting backlinks from other sources, such as submitting articles to article directories, exchanging links with other website owners, and so on.
