The technical part of high-fidelity prototyping is... making it interactive. Among the various tools that can make it happen, I chose to focus on Figma : its convenience largely balances the higher fidelity one could find using ProtoPie or similar tools. 

I use interactive components, frames, positions, overflows, variables, overlays and so on to make my designs as real as possible, and test and share them. 

These are the two reasons that make me use prototypes. First of all, it allows user testing and detecting flaws or improvements opportunities. And second, it allows to share concepts and ideas with teams with much more efficiency than static mockups.