The STAR principle is an excellent guide for structuring a rounded example/piece of evidence. It’s an acronym and corresponds to:

Situation – what was the situation, the setting?
Task – what was to be achieved, what was the goal?
Action – what did you do?
Result – what was the outcome, the result?

Here is an example,
A poor statement example:

‘I am an excellent leader and build high-performance teams’.

An improved statement is:

‘On taking up the position of National Sales Manager, I set up a team of 10 sales people based in three areas. By focusing on communication, motivation and goal-setting, we exceeded demanding sales targets in each of the four years that I held this position.’

By reviewing this statement you can clearly see how the STAR principle has been applied:

Situation: taking up the position of National Sales Manager
Task: set up a team of 10 sales people based in three areas
Action: focusing on communication, motivation and goal-setting
Result: exceeded demanding sales targets in each of the four years that I held this position.

While answers may not adhere to this format explicitly, evidence which shows appreciation of these four areas will be stronger and more balanced.