Here are a few things you can do.

• Add link to your website in relevant directories (non-spammy ones)
• Write guest posts on sites which has relavant content and add a link back to your website in it
• Join forums and communities which are revant to your website. Participate in them activitely and some of them will allow you to have a link back to your website in your signature (Just don't spam else you'll be kicked out)
• Add a blog to your website and write useful content relavent to your website which others find useful. If the content is really good, slowly people will start referring (linking) to it in discussions, blogs and so on.

nice

Here is a very good article on how you can build backlinks.

https://www.entrepreneur.com/article/247984

Nice try! Added a backlink while asking a question on backlinks :D