-Root (MIUI only, CM users can enable Root in Developer Options) Working on MIUI7 (thanks to @ss.suryakant95 for testing this out)
-Stock Recovery (just in case)
-EFS (IMEI) Backup and Restore
(Some users had problems unzipping this ZIP with WinRAR, consider using free alternatives such as 7-zip)
MAIN URL: Click here to download (Please use this download, but if in any case you can't extract, you may use the mirror I provided.)
MIRROR: Click here to download.
1. Enable Developer Options (Tap MIUI version 7 times in About Phone), and then in Developer Options, enable USB debugging.
2. Have you downloaded the ZIP? No? Download it, now.
3. Extract the downloaded ZIP wherever you like, keep in mind that all files must be kept together.
4. Connect your phone to the PC.
5. Run the Start.bat file.
ATTENTION: Please do a ROOT (I'll assume you're still in MIUI) before you flash TWRP, or you may be brought back into stock recovery. (Thanks to @omerjerk for testing this)
UPDATE: This toolkit's TWRP is deprecated (download the newest version here), but if you don't want to hassle with downloading another fastboot driver, you can still download dh.harald's recovery .img file, and copy your downloaded recovery to the extracted toolkit folder, then change dh.harald's recovery filename into twrp.img (UNTESTED)
I'll repack this toolkit with dh.harald's newest TWRP whenever possible.
This toolkit is made by magdag, all credits goes to him.