In case you are not an expert for creating a JSON schema (one of the elements of a data model)
On this page, you have a spreadsheet for helping with the first steps.
1.- Fill the spreadsheet with the names of the properties for your model
2.- fill the NGSI type (Property, Relationship or Geoproperty)
3.- In case of property, fill the data type (array and object types are currently not completely supported)
4.- Fill in the description
5.- Click the button, the page will reload
6.- voila! you have your json schema below the spreadsheet, just copy and paste into your favourite editor.