Within your partner tab in Office 365 you are able to manage tenancies on behalf of your clients. With this also comes the ability to do this via PowerShell as well but with limitations such as Exchange Online can’t be managed via this process, so to do this you need a seperate unlicensed admin account created to do this.
As you should all be familar with the web GUI I will discuss the required PowerShell commands to get started.
Once you have connected your service use the following cmdlet:
$tenID=(get-msolpartnercontract -domain customer.com).tenantId.guid
Then to get all users for example use:
get-msoluser -tenantID $tenID
all the other commands such as set-user are avaliable just ensure you include -tenantID $tenID to any commands!