Some theory of the First Conditional usage. I usually read the sheet of paper with the class together and ask them to make up their own examples according to each usage. Sometimes we have a competition - I give the beginning (condition) and the students have to finish it - who makes more endings - that person wins! Sometimes I give this bit of grammar as self-study and then ask students to teach me all that and sometimes I am a very "difficult= stupid" student - then several students go the whiteboard and start explaining - through that they learn the rules better than when I just teach them. The age and status of the student is not important in this case, believe me!