1. Identify the user's desired diagram type (flowchart, sequence, state, class, ER).
2. Obtain the Mermaid code, either from a file or user input.
3. Select the desired output format (SVG or ASCII).
4. Choose a theme or specify custom colors.
5. Execute the `render.mjs` script with the appropriate parameters.
6. Verify the output and provide it to the user.