How do I manually create groups in a group set?
Note: In group assignments, all students should be assigned to groups before the assignment is published. Grades and submissions may be affected for students who were not in a group at the time of assignment submission but who were later added to a group.
In Course Navigation, click the People link.
Add Group Set
Click the Add Group Set button.
Save Group Set
Add a name for the group set . Select whether you would like to allow self sign-up . Make sure the I'll create groups later option  is selected. Then click the Save button .
Name the group by typing in the Group Name field . If you want to limit groups to a specific size, enter the maximum number of group members in the Group Membership Limit field . Click the Save button .
Note: If your group set allows self sign-up and you set a group limit for the entire group set, the group limit will apply to each individual group you create. The option above allows you to modify the limitations within an individual group, such as changing one group to allow a few more members than the other groups. However, at a later time if you decide to edit the entire group set and change the group set limitations, Canvas will override all member limitations created within individual groups.