Best Practice for Cross Site Scripting(XSS)

[#1]

Any Best Practice Steps or policies for Cross Site Scripting(XSS) Vulnerabilites ?

I read an article in community. But, do not mention how to achieve in Edge with samples. Can you help me how to achieve in Edge with sample ?

• API Vulnerabilities and their mitigation in Apigee Edge

I read another document here saying "Examples of blacklist patterns" where Java Script Injection have pattern <\s*script\b[^>]*>[^<]+<\s*/\s*script\s*>. But, which policy will accept this ?

Thank You.