The first thing that you will need to do is enroll your devices in Apple's beta program. Notably, unlike the developer preview that requires an active developer account at a yearly charge of $99 (approximately Rs. 6,750), the public beta is available for free to all users who haven't registered for the developer account.
To do so, just sign in with your Apple ID, download the profile using Safari on your iPhone or iPad and proceed to install.
Although it won't be ready for its official release for a few more months, Apple has just dropped the first public beta for the upcoming iOS 12 update (read our hands-on impressions of the software here).
If you ask me, public beta software is a great way to try out upcoming features way before anyone else.
A word of warning: downloading the iOS 12 beta means taking a big risk that many things on your smartphone will stop working.
If you ever wish to roll back iOS 12 beta you can do so by unenrolling it through this link.
On an iPhone 6s and earlier, iPad, or iPod touch: Press and hold the Sleep/Wake and Home buttons at the same time.
Another new addition to scanning QR codes in iOS 12 is the yellow highlight frame shown below.
Apple has released iOS 12 and tvOS 12 public betas. You also can turn on Do Not Disturb when you're in a meeting, for a few hours or for longer. There are also updates to the Stocks app, Siri, Augmented Reality (AR), and iMessage. Specifically for iPhone X users, the new software update brings Memoji and an upgraded Messages app with Tongue Detection and Wink support for Animoji characters.
Apple didn't stop there, and added new power features as well.