A spectrum of new features are set for introduction when iOS 10 and macOS (n´e OS X) see public release this fall, but those brave enough to take the leap can test drive the software as part of Apple's Beta Software Program come July.
As announced earlier today, developers are the first to get access to Apple's beta software -- iOS 10, macOS Sierra, watchOS 3 -- and can download current builds via the company's Developer webpage. For public testers, Apple plans to make iOS 10 and macOS Sierra available next month.
To join the Apple Beta Software Program, go to Apple's dedicated webpage and sign in with your Apple ID. Users who do not yet have an Apple ID can create one for free. After agreeing to Apple's terms and conditions, enroll your devices to receive notifications of new updates and beta releases for download.
Once a member, all you need for download and installation is the latest version of iTunes. When the beta is released next month, simply connect an enrolled iOS device to an up-to-date computer and open iTunes, or alternatively run Software Update. Testers of macOS Sierra can access beta software from the Mac App Store.
As always, Apple's forthcoming betas are not recommended for work computers or daily use devices as installation comes with inherent risk. The beta program exists to work out the kinks prior to public release, meaning early versions of iOS 10 and macOS Sierra might not be completely stable.