How do I ask an elderly person for a donation?

We have been to the children's mansion and I'm going around snow lake and asking a lot of people for a donation but I have no idea on what to say (btw would someone help me out and give us a donation were having a contest on who can get the most $ we wanna get them like a DVD/VCR player and a tv and a lot of movies and personal care items and cover pillows and more so please help!