最初の手順
http://forum.xda-developers.com/oneplus-x/general/discussion-how-to-root-oneplus-x-t3242830
twrp
https://twrp.me/devices/oneplusx.html
OOSrom
http://downloads.oneplus.net/devices/oneplus-x/
https://s3.amazonaws.com/oxygenos.oneplus.net/055/OnePlusOxygen_14_OTA_010_all_201604021001_54d6bba8f7d84502.zip

お好みで
supersu
http://forum.xda-developers.com/showthread.php?t=1538053
xposed
http://forum.xda-developers.com/showthread.php?t=3034811
http://dl-xda.xposed.info/framework/sdk22/arm/

DPIはdefault480より420がいい