How to get my iPhone to DFU mode - please help me

Hello,

I hope you can help me, because i tried almost everything i could find in google, here what happened by order :

1 - I was getting searching, so i though it would be fixed if i update.

2 - I updated it from 10.3.2 to 10.3.3 .

3 - In the middle of the updating process, iTunes displayed an error.

4 - iPhone switched to recovery mode automatically.

5 - [pc] iTunes detected my phone and i tried to update it, failed.

6 - iTunes no more recognize it.

7 - Tried a macbook and it recognized it finally, but it failed to update, and no more recognize it again.

8 - I downloaded ReiBoot, my iPhone was recognized, i tried to remove recovery mode, it did.

9 - Now, when i turn on iPhone, it displays the logo for 5/7 seconds turns off, and keep doing this each time i press the power button.

Looking forward for your help !