Creating a Live Disk of My Installation??

Hello fellow Null-Bytians. I'm here with yet another question (yes, I know, we're getting quite tired with them). But however, I'm here to ask how on earth can I create a live disk ISO from my current Kali Linux installation? The only reason I haven't tried this myself yet is because I know that it's possible for me to screw up my entire install, and since I'm not running it on a VM, I can't roll it back.

I've recently went out and bought a 64GB Flash Drive. This flash drive has far more memory than my laptop does. (laptop has 45GB HDD) So, now that I've got my Kali Linux Installation on my laptop all customized, I don't want to go through all that customization again. I need to know how to turn it into a live disk (ISO file) so I can install it into my Flash drive and give it Persistence. Any help is appreciated!!! Thank you in advance!