How do I set out a write up of a experiment?

I’ve done an experiment “Workout the relationship between the period of oscillations and the mass attached to a spring?”

How should I write it up?

I will first write what was the task I was given. But I’m not too sure how to set out the rest of it.

I have to talk about the uncertainties inherent in the measurement, improving quality of measurement and making valid inference from the data.