To add your own strategy on Snapshot you need to fork the Snapshot.js repository and create pull request.
└── src└── strategies└── erc20-balance-of
npm run test --strategy=<STRATEGY NAME> // replace <STRATEGY NAME>
Have a look here on the requirements for adding a new strategy and make sure you full fill the points in the checklist: https://github.com/snapshot-labs/snapshot.js/issues/212
5. The snapshot team will review your PR and after it is approved it will be available in your space settings.