How do I disable Siri Suggestions in Spotlight Search in iOS 9?

iOS 9 adds an improved Spotlight search that utilizes Siri to suggest frequently used contacts, apps, news and other data. Some users are disabling this feature to speed up their devices, or because the information is annoying or irrelevant. Here's how to disable Siri Suggestions:

1. Open the Settings app on your device
2. Navigate to General > Spotlight Search
3. Tap the Siri Suggestions slider so it is OFF / WHITE