Custom recovery gives user access to do nandroid backup and other developer access.
Requirements :
1. Htc phone with unlocked bootloader.
2. A pc with htc drivers install (click here for the driver)
3. Download and unzip the android tools
4 . Download the recovery that belong to the phone here
5. Put the recovery file in the same folder as the extracted file.
6. Click on the cmd.exe
7. Now boot  the phone to bootloader either by pressing the power botton and vol. up key simutaneously or the following code on the cmd interface "adb reboot bootloader".

8. select hboot

9. And nw type "fastboot flash recovery recovery.img" (without the quotation marks). 

10. After you see success . Reboot d device to bootloader again and select recovery.

dats all u r free to go