Angry [Q] How to brick my galaxy with flashing custom staff?

HI,

i want to know how i can brick my device with flashing something with adb or twrp for example. The reason why i ask is, that every thing i want to try, someone says: WARNING! This could brick your device.

But as far as i know i can restore most things with recoverypartition or downloadmode.

F.e. i want to build a customkernel for Cyanogenmod. If i make it wrong, could i brick the device ?

So lets clarify this:

i have made a backup with efs Professional and selected all partitions (just to be sure)

from this point: how can i brick my device ?

Thanks for replies