I suggest you to build a links using content marketing strategies - Guest blogging, blogs, blogger page, using question and answers, eBooks, PDF, PPT
Image promotion -Infographics.
Social media links and use of social bookmarks.
Generating and submitting sitemap is one of the most important task in Onpage SEO practices. Sitemap is used to Notify Google to include your webpages to get indexed and crawled. Sitemap will let the Google robot see how pages.