If you love to have complete control of the way that every aspect of your phone looks then TWRP themes may be for you. If you love to flash roms like me then chances are you find yourself in twrp quite often. You may as well theme it and make it pretty to look at. Some excellent twrp themes have been released by dev "Primokorn". There are a few ways to install these. You can do it the manual way by moving the file into the theme directory of twrp, or you can flash one of the many flashable.zip themes. Either way your TWRP will be looking awesome in no time! Grab the four themes above and several others at the source link below.
Via XDA
Via XDA