Boot BeagleBone Black from SD Card

Dear friends,
i try for many times to boot my BBB from SD card with bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img but i can’t .Even the leds don’t blink.i dont know the reason .I followed all the steps to write the img through the SD and this step was successful.i follwed exactly this steps https://help.ubuntu.com/community/Installation/FromImgFiles (command line interface ).The problem is when i try to boot the bbb from SD card,any help plzzzz.
Regards
NADAL

Are you pressing the boot button on power up?

Gerald

followed all the steps to write the img through the SD and this step was successful.i follwed exactly this steps https://help.ubuntu.com/community/Installation/FromImgFiles (command line interface ).The problem is when i try to boot the bbb from SD card,any help plzzzz.
Regards
NADAL

Eh ? What are those instructions for ? You should be following the instructions from the page where you got the image from . . .

http://elinux.org/Beagleboard:Debian_On_BeagleBone_Black

Read the instructions carefully. Make sure to download / use a non flasher image. Which seems the one you have is fine.