How can we save our client’s websites from penalization or to be banned?
 

How can we save our client’s websites from penalization or to be banned?

When we search the name of website without www. or extension like .com or any other then if website appears in search then its not penalized nor banned and if we don’t find it then it may be penalized or banned.

You have to avoid below techniques while optimizing a site:

1. Over optimization
2. Black Hat SEO (Unethical SEO)
3. Low quality & Irrelevant backlinks
4. Buying backlinks
5. Disavow all low quality and bad links

I will avoid any kind of over optimization or black hat seo or unnatural methods for creating back links.

There are many causes for your site to be sanctioned and banned from google. Tell specific situation how your website.
You learn the options below
Step 1: Remove bad content
Step 2: Optimize the Onpage
Step 3: Stop for users to post
Step 4: Review the backlink
Step 5: Review of the article to see if content appears porn
Step 6: Register a new Webmaster Tools ac_count
Step 7: Make the website content for the category
Step 8: Submit the new posts to the forum

Is Keyword Density Still Important?
 

Is Keyword Density Still Important?

1. Avoid Excessive reciprocal links.
2. Avoid Duplicate content.

There are so many ways to check penalised or banned websites.
Check google Analytics And Google webmaster Tools

By using the white hat SEO techniques you can save the client's website. Even you can also warning by the Google that you can get from the web master tool.