Self-custody your own bitcoin keys but make sure you add in a real-world hassle to accessing them. Like splitting multisig in two different houses. Op vault codes where there's a time delay might help as well, allowing you to sleep on it.

I know I am prone to impulsive decisions, I can imagine a scenario where I can be psyoped to do some transaction in haste.

Honestly that's the only thing that scares me with self-custody.