Use a loop with serial read inside it. Wire 8 into Bytes to read. Whenever 8 bytes arrive in the serial buffer the buffer will return with them. Use String to Byte Array to recieve an array with 8 values and you can bundle them into a chart or a graph.
You can use the example finder (Help>>Find Examples) to find examples for serial communication and for multiplot graphs.
To learn more, I suggest you read the LabVIEW user manual. Also, try searching this site and google for LabVIEW tutorials.
Here is one you can start with and
here is another. You can also contact your local NI office and join one of their courses.
In addition, I suggest you read
the LabVIEW style guide.
___________________
Try to take over the world!