I'm in Life Insurance sales as well.
I find that I am networking almost every situation these days.
IE. Shopping in Wal-mart
I come across one of my clients in the dairy section, she has a child in her cart that I don't recognize, so I ask. Turns out this is her niece, and she introduces me to her little sister (now living with her) as her "life insurance lady" to which the little sister replies "OH, I have been meaning to look into that."
The big sister refers me by saying I would be able to work within her budget, I ask for a phone number and hand her my card.
"I'll give you a call next week. Does that work for you?"
"Sure!"
IE. Attending a Tupperware Party
One of my clients at the party asks a question about her mortgage insurance, then introduces me to a friend who is buying a house this year. I find out where she lives, then ask her if it's alright that I get her phone number from her other friend after Christmas, and she says, "that's great, thank you!"
These are two examples. Since I have developed rapport with existing clients, and their introductions of me to their friends are positive, it becomes easier to ask a few questions and then make a suggestion to call them at a later date. 