well i’ve had an undercut for sometime, different variations but always something short underneath. I also have VERY thick hair (curly too, believe it or not). thinning sheers are my best friend, about every 3-4 weeks i just go at it, few cuts through the middle and its so much lighter (don’t go too crazy here). I’ve also had the undercut go up pretty high and grown out the top a bit longer.
not the easiest to describe, but hope that helps! :)