Back Strength in Press Handstands

How does one go about building the back strength to do any type of press handstand? I can't even get the tucked press with straight arms yet. It may be a technique issue but I doubt it. Will negatives work better than anything else? Or is there something else I can do? Thanks

You could do straddle handstand presses, if those are too hard you can do headstand presses and if those are to hard as well you can do straddle ones.

Negatives should pretty much suffice.

Perhaps headstand inverted leg lifts, these aren't really that tough. However, doing inverted leg lifts while in a handstand on wall are an excellent drill, much tougher. You can also straddle these up.

Simple leg lifts while hanging are another good drill, be it on rings or bar.