iveI've been struggelingstruggling with the same problem but this works for me , You need to convert the .dmg image with power iso to iso. Then put the iso on a usb srick, drag it into your mac hard drive and mount it. Then u need to fornat your hsb stick with the disk utility tool. Make sure the usb is partioned as mac bootable then use use the image recovery and put your mounted osx iso into the source and your usb as the location. When its done restart your osx and press the option key:
- convert the .dmg image with power iso to iso
- put the iso on a usb stick (drag it into your mac hard drive and mount it)
- format your usb stick with the disk utility tool. (Make sure the usb is partitioned as mac bootable then use use the image recovery and put your mounted OS X iso into the source and your usb as the location.)
- restart your computer while holding down the option key
