Usually, when you purchase a pair of wireless earphones or a Bluetooth neckband, they have a partial battery charge so that you can switch them on and pair them directly to your iPhone immediately. However, if that is not the case and the Beats Flex earbuds do not turn on right out of the box, plugging them into a power source using the USB-C cable provided in the box is a good idea. Since the earbuds support quick charging, you can plug them in for a few minutes, and then they’ll have enough battery charge to connect them to your iPhone.
To pair, unlock your iPhone, enable Bluetooth, and then hold the Beats Flex earbuds close. Now, press and hold the power button on the neckband until the light indicator flashes in white, which means that the neckband is ready to connect. Within seconds, your iPhone should discover the Beats Flex earbuds and show an on-screen prompt with the name of the earbuds on top and a short animation (via Apple).
Tap on Connect toward the bottom of the prompt, and that is it — you have successfully paired your Beats Flex earbuds with your iPhone. Now, the prompt will show you the battery percentage left in the earbuds. Tap the Done button to wrap up the process. Once connected, the earbuds will also show up in the Bluetooth settings menu. With the Beats Flex earphones connected to your iPhone, you can use the in-line controls to control audio playback, change volume, answer or reject calls, and activate Siri.