There are a few methods for using multiple front panels. If you want to keep several panels open and operating at the same time, use subvi's that are called in parallel (where one does not have to finish for the others to be called). Set the window properties for these to 'Show front panel when called'
File | VI Properties | Appearance | Customize...
You can also set them to Floating if desired. If you want multiple panels, but only one to work at any given time you can make them Modal.
Try playing with those options and post a more detailed question if you get stuck.
