How to change date format from "MM/DD/YYYY" (US) to "DD/MM/YYYY" (UK) in SharePoint?

Scenario:
As clients reside in different countries, we need to change date format as per their current use. Recently I was given task to change date format from "MM/DD/YYYY" (US) to "DD/MM/YYYY" (UK).

Note:
Generally my blog contains warning after solution. But as this one affects wide range of settings, I would prefer that you first get approval for this.

Solution:

So the simplest way to achieve this is to change regional settings and SharePoint automatically change the date format accordingly. As I have told in note section, this will change each and every date in system to selected region format. So please get approval first. It may affect other settings too. But I am still not fully got aware where else this can affect.

So follow below steps to change regional settings:

• Log into your SharePoint Site as the Site Administrator
• Click Site Actions then Site Settings

• From the Site Administration section click Regional Settings

• Select English (United Kingdom) from the Locale: drop down box.

• Click OK.