You must be proactive, active and reactive to prevent or counter a negative SEO campaign. There is no way to completely safeguard your website and seo strategy completely from a negative campaign. What you can do is reduce the number of attack vectors to protect your website and your ever expanding online presence. There are three major areas of interest here. You need to protect your content, manage the backlinks and be aware of the user signals so you can remedy any vulnerable attack vector.

Hosting Infrastructure and Website Content

It is always better to have a dedicated server and dedicated IP. Shared hosting is relatively inexpensive. Most companies and individuals prefer shared hosting but if you have a website that is crucial for your business or at the crux of your sustainability then paying for dedicated hosting with an IP that is not shared by many websites hosted on the same server will go a long way to avert a negative SEO campaign.

Shared hosting makes a website vulnerable to the fallout of the weaknesses of other websites hosted on the same server. The same consequences are likely if you choose shared IP. A shared hosting service is an easy attack vector. A dedicated server and a dedicated IP make it harder for generic hacking attempts and negative SEO campaign to have the same effect. For instance, one or a few websites having malware will affect the reputation of other websites using the same server.

The next step is to choose a safer and more secured content management system. How you use a CMS will also influence your positive and negative SEO campaigns. There are content management systems that automatically archive pages and enable dofollow commenting. These are basically invitation for spam. You might be using WordPress and it is not immune to such problems. Fortunately, you can disable comments and archiving author pages. You can add noindex in order to tag pages. Your focus should be on ranking high value and authority pages. You do not want to prioritize ordinary pages or contents that are not your assets from the perspective of search engine optimization.

You should go for appropriate canonicalization with your content management system. This will prevent indexation of duplicate content, which is otherwise natural owing to pagination. You should also get rid of undesirable phrases in extensions and from specific pages. You do not want a website to get de-indexed due to some unintended mistake. Search engines are making their crawling rules increasingly strict and these may lead to de-indexing of a whole domain if you are not meticulous and proactive. You should reduce such risks by disallowing crawling of search pages. This will prevent indexation of such search pages. Simply use your CMS and Disallow: /search/, Disallow: /*?s= and Disallow: /*?q=. You may also disallow preview pages. Simply Disallow: *&preview=, Disallow: *?p= and Disallow: *&p=.

Do not become a victim of scraping. You should protect your content and take steps to ensure the published information is not reproduced or replicated as soon as they go live. You must use a reliable content protection service and safeguard the images and texts. Major search engines can trace the original source but you should still guard your website from parasitic hosts. You should use tools like Plagium or Copyscape to protect your content. You can request your webhost to report plagiarism. You can also file a complaint as per provisions of DMCA.

The Menace of Bad Links

Bad links are a problem. You may want user generated content but open comments and many such engagements are often abused. You may have to host a forum or community section. Have strict rules for all members. Ensure you enable nofollow attributes for all external and outgoing links. Compel the external links to get redirected through a page on your website so you can strip its equity. You can noindex the threads and actively moderate all outgoing or external links.

You should be promptly reactive with injected outbound links. Use Google Search Console to frequently and timely monitor outbound links on the website. Make sure they have not been placed by you. You can use a consistent crawling script to find and locate injected outbound links. You may rely on a cloaking software that uses reverse engineering to de-cloak injected links.

You must also assess the quality of inbound links. These actually cause more harm than the internal links on your website. Inbound links are beyond your control so they are trickier to manage or counter. What you can do is ensure there are more quality inbound links than poor ones. Try to get as many inbound links that are assuredly of a certain high quality so even if you have bad inbound links, there will be a net positive for your presence and the search engines will take that into cognizance. You must also observe the anchor text. Use more anchor text phrases. Disavow links as and when needed.

Monitor and Assess User Signals

There are many user signals that you should be constantly aware of. You may not be able to do much but being aware is the first step to knowing there is a problem and a potential negative SEO campaign. Monitor and assess the click through rate, bounce metricts and time on site. Use Google Analytics and Google Search Control to stay abreast of changing metrics.

Block botnet using a content delivery network or at your server and ensure you have a fast site at all times. Any sign of slowing down for no obvious reason such as phenomenal increase in traffic or server issue is perhaps owing to one or more unfavorable user signals. Avoid using a shaky or unreliable host and setup. Use CDN to prevent a DDoS attack. Remove unused plug-ins in your CMS and enable appropriate caching to prevent bandwidth wastage.

You should guard your website and optimization campaign from malware. Have malware protection and use the scanner frequently to know if you have been targeted. Search engines are becoming more conscious of how malware issues are being spread and they do not readily penalize all websites if the source is elsewhere but you should still be proactive and promptly responsive in your approach.