Remember the 4 H's, when someone is feeling upset they want one of four things from their listener, and asking up front "Which of the four Hs do you want right now" can really help get straight to supporting them.

Hear - Just listen, dont comment or try to fix it. Brief supportive statements like "I hear you." and "That sounds eeally tough." welcome, but dont insert unrelated topics.

Help - Give advice, including relating with a similar experience and specifically showing how it taught you something that applies to their situation.

Hold - Usually just listening, but with the addition of physical touch, could be holding hands or full on cuddling.

Hump (only for romantic partners) - cathartic release.