Informal Description

A popular method to model an information domain is to start with an informal, verbal description of the scenario:

A jazz musician is a person.
A person has a name and a birth date.
A jazz musician collaborates with other jazz musicians.
A jazz musician belongs to a style
(during a certain period of time).
Instrumentalists, jazz singers, jazz composers are jazz musicians.
An instrumentalist plays one or several instruments.
An instrument has parts, consisting of other parts.
An instrument has a color and a maker.
A saxophone is an instrument.
A saxophone has a mouthpiece.
A saxophone mouthpiece has a body and a reed.
A mouthpiece body has a maker.
Mouthpiece, mouthpiece body and reed are instrument parts.
A reed has a maker and a grade.
A jam session is a form of collaboration.
A jam session is performed at a location and at a particular time.
A project is a form of collaboration
(during a certain period of time).
A band is a form of a collaboration
(during a certain period of time).
A collaboration can result in one or several albums.
An album has an album number and a title.
An album has one or several tracks.
Albums or jazz musicians are reviewed by critics.
A review has a publication date, a URL and some text.
A critic is a person.

The actual relationships are, as a matter of fact, much more complicated. For example we could include a full taxonomy for musical instruments and styles. But for the purpose of this introduction to conceptual modeling, the above description is adequate.

A simple grammatical analysis can identify nouns (Jazz musician, Person, Name, Birth Date, Band, Collaboration, Location, Album, etc.) and verbs (is, has, collaborate, plays, etc.) in each sentence. This step helps us to identify relevant information items of the conceptual model.

Tip:
Always use simple sentences.