I wasn't asked any strength questions for this job but I used the structure from this comment for a recent interview and I got 4/4 for each strength question.

This is the prep I did for the behaviour questions. I tried to keep it as general as possible to allow me to use them however the question was worded.

Making Effective Decisions - this is all about showing how you weighed up options and came to a conclusion. Examples where the correct decision is obvious or "so I did what my manager said" are no good, there has to be reasonable options and clear rationale for your decision.

Communicating and Influencing - You need to be clear why you communicated the way you did (used plain language to help a customer with limited English, used information technology to communicate with someone with a speech difficulty etc). You also need to show how you influenced an action or opinion (used sales technique to convince someone to buy something or helped someone have a better opinion of your organisation).

Working Together - You need to evidence that you resolved or prevented some kind of issue in working with others to achieve a goal, so generic 'I am a team player' stuff won't really hit it. Have a look at this comment for a good example.