The competencies vary between employers as they will be looking at different aspects depending on the actual job and they normally allow you to use examples outwith work. The important thing to concentrate on is the part YOU played so don't say "we did this and then we did that"
A lot of folk do things without thinking of the processes involved but things don't just happen by themselves. Have a look at each competency and think of an example (it helps if you can think of a different example for each one) and also another one in case they ask you to think of one more during the actual interview.
A friend of mines had to give an example of planning and she used the example of when she got her mum's kitchen and bathroom done up. She had to choose the builders, get the fixtures and fittings sourced made sure the delivery dates were stuck to, checked on the progress of the work etc.
If there is a word limit stick to it (they may ignore anything past the limit.) It's often a case of writing it out a few times and cutting out the waffle. Also if you're using an example not connected with the current employer, don't use technical words or jargon assuming they will know what you mean.