1. In Grafana dashboard, navigate to the appropriate data source.
2. Use queries or metrics to retrieve the size information of the database or table.
3. Customize the dashboard to display the size metrics in a clear and understandable format.

Example:

SELECT pg_size_pretty(pg_database_size('dev')) AS database_size;

SELECT pg_size_pretty(pg_total_relation_size('your_table')) AS table_size;