There are many ways with which you can reduce the spam score of a website.
- Disvow the spammy links with help from Google Webmasters Tools.
- Re-phrase your existing content and make it high quality
- Also, check for the alt-txt of the images
- SEO needs be top notch
- Make sure to get backlinks for high quality and relevant websites.
- Do not give too many backlinks to other websites
- Also make sure to add backlinks to your website content in a natural way.