What are your tricks?

[Zincubus]

Not that my BP will take a f/t rat regardless of where I hold it, but... Holding it by the back of the neck will make the heat signature look more like a live mouse than the weird vertical posture it'd have being dangled upside down.
You wouldn't think that'd make a huge difference, but I have a couple snakes (non-BP) that have to have food offered held behind the neck. If they can't figure out where the head is supposed to be, they just freak out and refuse to eat.

That's interesting , I use tongs and hold by the end of the tail just so they don't bite onto the tongs ..