How do I know my NPT size?

Hello there, I'm curious about how I can determine the size of my NFT (Non-Fungible Token). I've heard that the size of an NFT can impact its storage, transfer speed, and potentially even its value. Could you please explain to me the process of finding out the size of my NFT, and what factors might affect its size? Also, is there any best practice or recommendation for optimizing the size of an NFT for better performance and efficiency? Thank you in advance for your help.