1. Download Nougat 7.1.1 Lineage OS for YU Yuphoria
Android 7.1.1 Nougat is a major update so, it is required by the Lineage Team to connect your YU Yuphoria to a Wi-Fi network to be able to download the ROM with high speed.
Download Lineage OS for YU Yuphoria (Will Be Provided Soon)
2. Download Nougat Lineage OS Gapps
Since, you are interested to update your YU Yuphoria to Android 7.1.1 Nougat using a custom ROM as it is Lineage OS ROM you need to download and flash Google Apps in order to be able to use any Google services.
Download Nougat Lineage OS Gapps
3. Flash Nougat 7.1.1 Lineage OS on YU Yuphoria
How to Flash Nougat 7.1.1 Lineage OS on YU Yuphoria? Here it is:
At first, download files from above and transfer them to your phone’s internal storage. Do not unzip or extract anything from there.
Now, switch off your YU Yuphoria completely and once hear a vibrate on your hands after 5-10 seconds boot it into recovery mode.
When, you are into a recovery mode like TWRP you need to hard/factory reset your YU Yuphoria. From the TWRP main menu tap on the wipe button and swipe to the right side to complete the operation.
After doing so, tap on the install option from the TWRP main menu and load the Android 7.1.1 Nougat Custom ROM file for your YU Yuphoria.
This time repeat the last step from above but install Lineage OS Gapps package.
When done, go back to main menu of recovery and reboot it.
Good Job; Now you know all the steps that you had to take in order to successfully install or flash Nougat 7.1.1 Lineage OS on YU Yuphoria device.
Have any help or question? Don't hesitate to use the comments box.