Flashing ROMs without SD card, newbie question

[kannon30]

I have an HTC One and want to flash it to another ROM. Currently it's unlocked and rooted, so a lot of work is already done. My concern is saving the backed up version of my current ROM in case things go haywire. On other phones I've simply saved it to the SD card and restored it should the need arise. Currently with my HTC One, I don't have an external place to store the backup when I wipe the device to properly install a new version. While the new ROM should work fine, I want to be safe. Any ideas as to how to handle the backup so I don't end up with a bricked phone?

Thanks

 

[UJ95x]

I have an HTC One and want to flash it to another ROM. Currently it's unlocked and rooted, so a lot of work is already done. My concern is saving the backed up version of my current ROM in case things go haywire. On other phones I've simply saved it to the SD card and restored it should the need arise. Currently with my HTC One, I don't have an external place to store the backup when I wipe the device to properly install a new version. While the new ROM should work fine, I want to be safe. Any ideas as to how to handle the backup so I don't end up with a bricked phone?

Thanks

Welcome to Android Central
I'd make a Nandroid backup and save it to the internal storage, then maybe borrow someone's PC and use that to transfer it to an SD card if you have one. You can't really do much else since SD cards aren't supported. You'd just have another copy of the nandroid if the one on the phone were to get corrupted somehow

Sent from my Galaxy S4 running Slim Bean 4.3

 

[velvetelvis]

Can you use an otg cable and a thumb drive?