Do it scared
Do it scared. Do it anxious. You don't have to do it happy, but you do have to do it.
You may have heard something like this on social media, and it's something I've definitely done and said. Sometimes you know your anxiety or depression is stopping you from doing something that will make you feel better, so you do it anyway, pushing through the resistance.
I've been using it as an excuse. If I can do it anxious, I don't need to look at my anxiety. I can be flippant to the how and why of my feelings and push through to action, which will then lower the anxiety, by providing something that feels like control.
Anxiety doesn't like ambiguity or the unknown, so you do things to make thing clear and known. You take control of a situation, even if it's not related to the one causing anxiety, and it feels like competence. You can affect change, and you can make a mark or have control somewhere, so maybe it'll all be okay.