It's quite quick to create a bootable installation USB from Mac OS 10.11 El Capitan.DMG using TransMac on Windows PC.
- Download Mac OS X El Capitan.DMG from here.
- Download TransMac trial.
- Run TransMac by "Run as Administrator".
From the left pane, select the USB, right mouse then choose Restore with Disk Image
From the warning dialog box, just click on Yes, in the new Window, Locate and browse for the El Capitan.DMG file
The whole process will finish in minutes