I've already made preliminary research about the standard. The below link seem to describe it very well: https://docs.cardano.org/en/latest/native-tokens/using-the-token-registry/token-registry.html However, I'd like to ask whether or not is it safe to follow the instructions in the above link when creating my own native assets in Cardano Mainnet? Has anyone have tried to create tokens according to this standard procedure?
As of now, there is no metadata standard/CIP defined for native tokens. But you can follow this CIP PR to know a bit of how the community is trying to define a standard for the same (your inputs are welcome).
Also, you can follow the metadata of some of the NFTs currently live to follow the schematics in case you are going to build a project.
Cardano Improvement Proposal called CIP25 defines NFT Metadata Standard.