Bipolar/depression- what's the best way to help them during their depressed episodes they go through? how can i be a supportive person?

Listen and support: I think it is most important to continue to encourage them to stay connected with both their psychiatric treatment as well as their social support system as disruption of either can lead to deterioration. Medicines can be essential to stability although it can also be helpful to make sure they are able to get the essentials like getting enough sleep! being authentic and listening can help.