How to mitigate the threats ?

See more:

web_development

Hi How to mitigate the threats

I have a website will store sensitive information in
the database(My SQL).The website will accept credit card payments but
the actual payment process will be sent to an external payment gateway.

The most important thing is the security of the database information.
So I want to know how best to protect the website from the typical web
security threats as well as practical steps on how to mitigate these
threats given the technical details please .

Thanks

Raj