Start the transaction using the menu path or transaction code KCH2

Double-click

Enter the group you want to update and 

Click on the group you want to include a new group. and click  or 

Enter the code & description of the new group in the blank raw that appeared and click   . The group is created.

Create all groups & sub-groups 

Save 

There is a message at the bottom of the page 

You can leave the transaction 

If you want to update the description in another language, you must log in the language requested