Invite a teammate
In the top-right corner of your Dashboard click your workspace name.
Choose Team members in the dropdown.
You will see the list of all your current team members, and the Invite new member button below it. Click it, enter the email address of your new teammate and click Invite . Shake will send an email invitation to that address.
Delete a teammate
Only if you have an Admin role in your workspace, you can delete someone. It's also done from the My team members section. Just click the red X button next to a person. Removed teammates are permanently deleted.