Say the other station's call sign once, followed by "this is," then your call sign given phonetically 

Say the other station's call sign at least three times, followed by "this is," then your call sign at least five times phonetically

Say the other station's call sign at least five times phonetically, followed by "this is," then your call sign at least once

Say the other station's call sign at least ten times, followed by "this is," then your call sign at least twice



4