How to collect data from individuals

Researchers and clinical professionals use participant observation when they want to collect data from individuals who they have a relationship or role with and/or when they want to be able to interact with participants. Examples include a teacher collecting data from students, a bartender collecting data from patrons, or a researcher joining a support group and collecting data from other group members. Participant observation can be disguised, where those observed are unaware that data is being collected, or undisguised.
Think of a topic or scenario that could be used for a participant observation, and please respond to the following:
How does participant observation differ from naturalistic observation? What would you want to study and why would this be good to study with a participant observation? Summarize how you could conduct a participant observation to assess this. Would you use disguised or undisguised participant observation? Why?