How can I buy ADA?

I'm interested in investing in Cardano's native cryptocurrency, ADA. Could you provide me with a step-by-step guide on how to buy it? I'm not very familiar with the process and would appreciate any advice you could offer. Specifically, I'd like to know which cryptocurrency exchanges support ADA trading, what payment methods are available, and any additional considerations I should be aware of before making a purchase. Your insight into the crypto market and ADA specifically would be invaluable to me as a potential new investor.