Usually you just have to hold the power button to put Bluetooth headphones into pairing mode. If that doesn’t work, check the manual that came with your headphones. An LED indicator typically flashes blue and red or you’ll hear a noise through the headphones when they’re ready to roll.
For this tutorial, I have a set of VAVA MOOV 28 Bluetooth headphones. They retail for about $30 and offer pretty solid battery life, can take calls, let you access Siri and more.
You can splurge, too, if you want to spend more for great sound and other features. I also own a set of Bose QC35 Bluetooth headphones that are great for noise canceling and long plane rides but cost about $400.
Source: Tech CNBC
So you just bought a phone with no headphone jack — here's how to use wireless Bluetooth headphones