I'd say that persuading someone to learn is very difficult. They need to want to learn. They need either intrinsic and/or extrinsic motivation to want to learn.
1) Money - Financial incentive to learning
2) Employer providing time off to learn
3) Learners lottery - open to people on Welsh courses
4) Awards - more competitions (chances to win awards) for Welsh learning efforts
5) Fame - more chances for Welsh learners to get on TV
1) Inspire! e.g. Promote Welsh language music
2) Inspire! e.g. Promote Welsh language cultural events
3) Inspire! e.g. Learners profiles TV programme giving loads of reasons to learn, people expressing how much they enjoy learning.