1. Lessons aren't mandatory. You need them to cast even the most basic spells, though. If you want a lesson- you'll have to ask the Master (me) for a lesson, these will be private unless requested otherwise.
2. You won't necessarily need to ask for lessons- sometimes group lessons will be offered, and in that situation either a topic alerting all fire mages will be posted or an email will be sent. These aren't mandatory, but if your character doesn't attend you can't use the information offered there.
3. During lessons feel free to ask questions. It's like at school- they keep saying "If you're confused, there's a good chance at least 5 other people are"; it's actually true.