To design degenerate dimensions effectively, you need to follow some best practices and guidelines. First, you need to identify which values are candidates for degenerate dimensions, and which ones are better suited for regular dimensions. A good rule of thumb is to use degenerate dimensions for values that are natural keys or surrogate keys of the source system, and that have no descriptive attributes or hierarchies. For example, transaction numbers, invoice numbers, or ticket numbers are good candidates for degenerate dimensions, while customer numbers, product codes, or store codes are better suited for regular dimensions. Second, you need to ensure that degenerate dimensions are unique, consistent, and meaningful within each fact table. You can use techniques such as concatenation, padding, or hashing to create unique and consistent keys for degenerate dimensions, and avoid using meaningless or arbitrary values. Third, you need to name and label degenerate dimensions clearly and consistently across the data warehouse. You can use prefixes or suffixes to indicate that a column is a degenerate dimension, such as TXN_NUM or INVOICE_KEY, and use descriptive names that reflect the business context and meaning of the value.