How to restrict storage access (USB, DVDs and External HDD)

It is important to protect user and business files from competitors or vigilantes or even your staff members.
Together we will create a policy that is mostly used on computers that has sensitive information and is shared amongst multiple users.

What does the policy do ?
It restricts access to specified devices.

Guide:

Search & Open Microsoft Management Console (MMC)
File > Add/Remove Snap-in
Add Group Policy Object Editor (gpedit) > Browse Users > Non-Admin Users (Ideally or you can direct the policy to any user or group )
User Configuration > Administrative Templates > System > Removable Storage Access

Here you can select what policy to apply.
Just select what policy to apply and select enabled.

If you would like to restrict Storage Access on everyone including yourself, follow the steps below:

Search & Open Group Policy Object Editor (gpedit.msc)
User Configuration/Computer Configuration > Administrative Templates > System > Removable Storage Access

And simply select the policy you want to apply.