I started many years ago by taking one child at a time with me to BYU games. When they were young they were more interested in snow-cones and snacks. Before the football, I did the weekly grocery shopping and took one child at a time. We live in SLC so with travel it really was a day out with dad. We sat at the top of the north endzone. Father/child bonding time.
Now 20 years later they are all in their mid 20's, two are BYU graduates, and they ALL come with their spouses to all the home games and I have to buy 8 tickets each year (of course they pay for their own but I buy to keep us together).
They are more rabid fans than I am by far. I don't for a minute think that it would have happened by just watching the games on TV.
It was the in person experience that made it happen! They fell in love with the game and the atmosphere. My daughters and my wife attend the BYU Women's football camp and last year we took my 78 year old mom to the camp. She was so impressed with Bronco and the program, that this year she is also coming to the games with us.
Good luck!!!