Hello,
you haven't specified when you want to provide variables into the process. But you have several options:
1.) you can pass your variables when starting your business process instances
2.) you can use global variables of knowledge session
3.) you can pass data through signalling an event
I recommend you reading the docs:
http://docs.jboss.org/jbpm/v5.3/userguide/ch.core-basics.html#sec.data