Today, Apple has released the first iOS 13 and iPadOS Public Beta updates, allowing non-developer users to participate in the test. So you can download and install easily on your iPhone or iPad, without much tricks like before.
Apple initially said that iOS 13 and iPadOS Public Beta updates will be released in July, but it will bring users a few days earlier. The test program registration page and the beta.apple.com profile download last night were overwhelmed, due to too many visitors.
To be able to download and install iOS 13 Public Beta, you will need to access the beta.apple.com link to register the test program with your Apple ID account.
Then switch to the iOS tab and select "Enroll your iOS device". On your iPhone, scroll down to the Install Profile section and download the profile of iOS 13 Public Beta to your device.
Before installing the iOS 13 Public Beta version, you should backup your device using iTunes. Then go to Settings and see the download profile, click to install.
Once completed, you can download and update iOS 13 Public Beta just like any other iOS version. By going to Settings> General> Software Update.
The steps are similar to iPadOS.
Note iOS 13 only supports iPhone 6s / 6s Plus and above. And iPadOS only supports iPad Pro, iPad (Gen 6), iPad (Gen 5), iPad mini 2019, iPad mini 4, iPad Air 2019 and iPad Air 2.