You can approach in the following method for SAP testing.
1. Transaction Testing: Testing a single transaction (e.g. VA01 Create Sales Order).
2. In-Stream Testing: Testing of a flow within 1 single process. In-Stream Testing is testing chains of transactions that flow together and which reflect important business process and scenarios
3. Cross-Stream Testing: End-to-end testing of integrated processes through execution of predefined business flows.
4. Acceptance Testing: In-Stream or Cross-Stream Tests by the user community with the objective of formal acceptance. In some cases, and for practical reasons, the Acceptance Tests are combined with Cross- or even In-Stream Tests.
