How do I buy an ordinal?

I'm a newcomer to the cryptocurrency scene and have heard of ordinals being a unique asset class. Could you please explain in simple terms how I can purchase an ordinal? I'm particularly interested in understanding the steps involved, from choosing a platform to making the actual purchase. Additionally, are there any specific considerations or risks I should be aware of before investing in ordinals? I'd appreciate a clear and concise guide to help me navigate this process.