1) you can increase the authority of your content by creating the backlinks of your content and these backlinks can be then shared or link with other higher authority and high quality content. content will help the search engine to in crease your credibility and your authority.
2) You can take the help of other well-known influencers which can help you in sharing and promoting your content. Here the influencer will act as the nominee of the content. This will help you in increasing the reach of your content. This will eventually helps you in increasing your SEO ratings.
3) Promote your content with the help of other channels like social media. This will help you in getting a good traffic on your website. Once you will be getting good traffic, your SEO ratings will go upwards automatically.