Xiaomi has started the rollout for the MIUI 8 global beta ROM. Select devices from the company will be getting the update today, and the rest of the supported devices will follow.
Those on the MIUI Global Developer ROM have it the easiest, as they can just download the OTA update. Those on the Alpha ROM will have to first flash the Developer ROM and then install the OTA update. Those on stable ROMs will have to first unlock the bootloader and then manually flash the ROM.
We have covered all the new features of MIUI 8 in our previous post.
You will find all the instructions needed to flash your device from the link below.