You can put voice directions on your iPhone map by following these steps:
1. Open the Maps app on your iPhone.
2. Tap the Directions button at the bottom of the screen.
3. Select the starting point and destination for your route.
4. Tap the Route Options button at the bottom of the screen.
5. Select the Voice Guidance option.
6. Select the type of voice guidance you'd like to use.
If you need more help, you can refer to Apple's support website for more information and instructions on using the Maps app on your iPhone.