Below is just a general method of entering safe mode & may not be specifically for your huawei model but the method doesn't usually differ too much so its worth a try. Hopefully it works for you!
When switching on the phone, press and hold the volume down button and the phone will enter safe mode.
When the phone is switched on, if you press and hold the power button and select Power off in the displayed menu, the system will display a Reboot to safe mode dialog box. Touch OK to restart your phone and enter safe mode.
After entering safe mode, a prompt will be displayed in the lower left corner of the screen.
Some phone models do not support safe mode.