Incorporating Buttons into Multiple Procedures?

[Kenster102.5]

I am creating this program with an interface, and a picture a car, this program will control the output to lights of the model car via "parallel put". This output will come later but I need to incorporate buttons for the interface, and I am using 3 procedures currently, 1 for headlight, one for tailight, for the front turnsignal. How to I incorporate buttons to trigger these procedures, is there a tutorial for buttons in multiple procedures? The attached picture is used as the schematic for the interface, since I am using Pic.Screenload.
Thanks Ken