SAP SD - Enterprise Structure.

I am not going into detailed procedure of creating ES. But I am giving you ES image. Let us see how the ES of a company looks like.

SAP SD - Material Master.

Here in Master Data after the CM, Material Master is another data existing in the system. Before creating Material Master Prerequisites are Assigning Company code to fiscal year variant (FI role), Assigning Chart of Accounts to company code (FI role). Maintain Company codes for Materials management. (MM role), Define Material types (MM role).
Here SD roles starts to enter Material Master Data. Following images will guide us to create MM.(Before Last image save the configuration).

SAP SD - Customer Master.

Here; I am giving you the image to give us idea about creation of Customer Master (Data).
We need Account group, Number range, Partner Determination Procedure to be assigned.
Use standard group for practice (ex: '001-sold to party') .
Created number range '09' and assigned to above Account group.
Let us see how the Customer Master will be created. Following images will guide you to create CM