Question

How do observing and inferring differ?

Answer 1

Observation = you are seeing it as in: I can physically see rain therefore it IS raining
Inference = making a point based on suggestions as in: there are puddles on the ground. It must be raining therefore it IS raining

Answer 2

Observing is commenting on what you see e.g: It is raining.
Inferring is drawing conclusions from observations for example you see the road is wet so you might infer that it rained last night.