I was wondering has anyone tried this?

I wasn't successful in booting my BBB with it.
Im not a linux expert but i know relatively some so maybe ive done something wrong or maybe i haven't done something or i miss something important.
But this is what i did,
1. I download the image
2. unzip it
3. dd the image to sd card using bs=512k and also tried bs=1m
4. insert sd and turn on while holding boot button

Result: just a lit power led. no lit user led.

my question is, does it use the user leds to indicate activities? Im booting it headless so i assume i can ssh or screen.

I dont use serial too so i dont know whats going on while it boots or whether its booting. I have a serial cable but im using mac mini with yosemite and I believe the driver for the cable has problems with the latest OS so i cant use it.

I hope someone can help me who have tried this on BBB. Thanks in advance guys.