You want to send out an SMS to a select group of users, this is the most efficient way to communicate with your team.
Here is what you need to do:
You need to make sure that your users that you are wanting to create the SMS group all have the same user tag. If you are using contacts, please tag all your contacts with the same tag. A great example is all your Truck Drivers get tagged with Truck Driver.
Go into the SMS Module and click Contact Group you need to put in what you want to call the group.
Select whether you are sending to Fieldworkers or Contacts
Select the tag that you added to the users in step 1.