Jayapataka Swami: There is no hard and fast rule. There are many systems to engage the youths. There are preaching programs and various programs to engage the youths and one can try these. Also, to listen to the youths and then to preach to them, the thing that would engage them in something they would like to do. Say if someone likes to do IT, then he can do IT for Krsna. Or if they like to do some finance, they can do finance for Krsna. If they like to do Medicine, they can do Medicine for Krsna. The idea is to engage the students in doing what they like to do. And then when they become fully surrendered, they can do anything for Krsna, but initially have them do something that they are comfortable with. Hare Krsna!