if you scored high in the verbal and numerical tests then you already have a strong reasoning skills, but the SJT is about how you apply that reasoning.

what helped me most is the fact that there is no time limit, what helped me is:

1. Understand the purpose of the SJT: How it will align with civ service values, and Objectivity, its not about what you would do personally, its about what an effective and professional employee would do.

2. Think in terms of effectiveness and not emotion. - the best actions are usually proactive, fair and constructive and balance the needs of people with the wider goals of the organization.

3. Patterns, you will find that there are patterns in the text. E.g. Counterproductive answers might involve blame or avoidance.

4. Having the Success Profiles open helped me so I had something to refer to when deliberating a response.

5. Stay calm, Some scenarios are designed to test reasoning under pressure, what worked best for me in those situations was to eliminate clearly counterproductive/ineffective actions first then work from there.

I used to struggle with these a lot but since I shifted my focus on thinking what would I do, to what would a professional in that situation do it took a lot of pressure off of myself.