Get started. Ask yourself whether you can resolve a problem there and then. If so, do it. If not, follow Einstein's approach: 'Make it as simple as possible, but no simpler.'
Define the problem. In one sentence, write down what you have to make a decision about. If you've been headhunted, what's the crux of your problem? Is it whether you actually want a new job?
Explore what's involved. Who and what will be affected, when and where will the outcome be implemented, and why do you even need to make the decision? You may have to consider family and colleagues, lifestyle and aspirations. Delve deep so nothing gets overlooked.