Import a template into a test copy and read its inputs, outputs, permissions, and side effects before running it. Replace any embedded credentials or account-specific destinations, then test with harmless sample data.
Keep the original template available. Make one change, run a known case, and compare the output with the previous version. When a step fails, inspect its input rather than changing several nodes at once. Check how retries behave, especially if the template sends messages or appends records.
Remove nodes you do not need only after the basic flow works and its dependencies are clear.
Akousa