Understand the different paradigms that you can use in LabVIEW to move data from place to place, such as dataflow, buffers, and variables.

Data Communication Methods in LabVIEW
LabVIEW contains many data communication methods, each suited for a certain use case. Refer to the overview to ensure you implement the correct data communication method for your application.
Local Variables, Global Variables, and the Feedback Node
Local variables and global variables share data when wires cannot connect locations in a LabVIEW application. The Feedback Node stores data from a previous loop or VI execution.
Transferring Data over a Network with LabVIEW
When choosing networking features for your LabVIEW applications, the most important factors are the communication models that your applications use. Understand the available communication models, their data transfer requirements, and the features that fulfill those requirements.
Communicating Data Between Parallel Sections of Code Using Channel Wires
A channel wire is a wire in LabVIEW that represents asynchronous communication between two parallel sections of code without forcing an execution order. Channel wires don't require refnum management and require fewer block diagram nodes than queues.

Related information:

LabVIEW User Manual