Within Shiptheory, your orders can have multiple statuses such as Complete, Ignored, Failed and more. You can see more information on all these statuses here: Shipping Statuses

One of these statuses is Waiting. There's a tab in your Shiptheory dashboard for this specifically called "Waiting to Ship":

There are a few reasons that you may want to have a shipment marked as "Waiting"; the first is if you don't want shipments to book automatically. For example, if you're unsure of the service a shipment may need to book in with at the time it comes through, or if the details of a shipment may change, you may want shipments to sit in "Waiting" until you've confirmed the situation with them. 

Another reason may be that you want to update orders coming into Shiptheory but don't want them to immediately book in. For example, if you use a rule to update the shipment information, that rule could then be set to have the order sit in "Waiting" for you to then do with as you will. For some more information on updating rules, please see here.

You can also use the Shiptheory package sizes with specific carriers to specify package sizes in an order. For this, you would want to have the orders marked as "waiting" for you to then update them. Please see some more information on that here. 

See below for the different ways to have an order set to "Waiting";

Mark For Approval Rule

As per the guide linked above, you can have orders "mark for approval" when matching a rule rather than booking straight in. With this, you would set the carrier, service and criteria as usual, but then hit "advanced settings" at the bottom:

Leave Service Blank Rule

If don't have a specific service in mind, then rather than use the "mark for approval", you can set the rule up as usual, but only select the carrier and leave the service as blank, orders will still match the rule, but won't auto book in and will rather sit in "Waiting":

If you have any questions or issues with this, please feel free to Contact Support.