You need to find a way to improve a website's search engine rankings that occur outside of the website itself. One of the most effective off-page SEO tips is to focus on building quality backlinks from other reputable websites in your industry. This can be achieved by creating valuable content that other websites will want to link to. The other options that can help to improve your website's off-page SEO include social media marketing, guest blogging, and influencer outreach.
Of course, you can do this work by yourself, but it will require skills and time. You need to decide whether you are ready to wait and learn all this stuff or whether it is better to hire professionals. I personally chose the second variant and addressed https://rankengine.com/. Great service at a reasonable price, so no regrets.
Hopefully, this info will be useful for you. Good luck!