Details on the Implementation Phase 

See:

Transaction Model for Developing BAPIs

Providing Input Help (F4 Help)

Problems with APPENDs and INCLUDEs in BAPI Data Structures

Example: Choice of BAPI Data Structures

Internal and External Data Formats

Naming the Function Module and the Function Module Group

Determining the Object Type and Its Key Fields

Example: BOR and Function Module Parameters

Example: BAPI Interface and Function Module

Releasing the BAPI