Shame on me, I’m not yet wearing a helmet – however I will soon.
Q: Which headgear would you recommand for wearing underneath a road cycling helmet?

Can one still wear a regular hat, e.g. (merino wool) beanie? Or, is a ‘helmet cap’ or bandana (that seems to made specifically for the purpose) the best way to go? I especially like something that counteracts sweat (breathable) AND also covers one’s ears effectively. Love to have spring (chilly) and winter (cold to severe) options.