I cook for 100 people at a daycare center and I'm going to attempt to make chili from scratch?

I have several cans of beans and chili spice and other spices, but I really don't know what to do. What direction I have says to make 5 lbs of beef and add clili beans. How much spice do I use, I brown the beef and put it in the slow cooker, and then what. Its a big double sided crock pot like two crock pots together