The first stop to the scientific method is to do find a purpose.
Do your research on the purpose you decided to do.
After you do research then you form a hypothesis.
Finally you get to do the fun thing. CONDUCT THE EXPERIMENT.
Finally collect the data from the experiment and look over your hypothesis and revise it if needed.
A qualitative observation is an observation that you make by using your 5 senses. For example the dog is black.
A quantitative observation is an observation you made by measuring something. For example the dog is 3 feet long.
An Inference is something you think happened based on your observations.
An observation is something you see, hear, smell, taste or touch.