With MyCrypto, it's possible to receive any Ethereum-based token by simply sending it to your Ethereum address. By default, MyCrypto will try to look for the most popular tokens in your address, but it might not always find every single token you own. In this case it's possible to manually add it to your interface.
The way that tokens work on the Ethereum blockchain, is that each token is a smart contract, which hold its own data and records. When you 'receive' a token, it basically means that the smart contract has a record of your address owning this token. MyCrypto will query the smart contracts for any tokens on your address, and show every token with a balance.
Make sure that you do NOT send your tokens directly to the token contract address, or you will lose them forever.