How do I pay my LRT?

Excuse me, I'm a bit confused about how to pay for my LRT ride. Could you please explain the process to me? Do I need to have a specific type of card or can I use cash? And if I'm using a card, how do I go about topping it up with funds? Additionally, are there any discounts or promotions I should be aware of that could help me save money on my LRT rides? Thank you in advance for your help with this.