What are concrete examples of expressing vulnerability?

Admitting a mistake and apologizing
Admitting a mistake and apologizing demonstrates vulnerability. It also means that you accept responsibility for the mistake you made. Doing this shows that you are human and that you are willing to learn from the mistake you made.

Expressing emotions
Openly expressing emotions, you feel, is a form of vulnerability. This involves being honest about emotions, you feel, and not suppressing or hiding them. Example # 1: Revealing that you really like a person and feel love in your heart for the person can be one of the most vulnerable things you can do – especially if you do not know how the person will respond. Example # 2: If you feel fear about doing something, you show vulnerability by communicating to people that you feel fear of doing this and describing needs you have. Openly expressing the fear, you feel, shows that you are not trying to appear perfect.

Doing new things and/or doing things differently
Stepping outside your comfort zone to a) do something you have not tried before, or b) do things in a new way can be a way to express vulnerability. Breaking the status quo by doing something new and/or doing things in a new way can help you learn and grow.

Sharing personal struggles
Sharing experiences of difficulties, problems, traumas or abuse you experience can be a very vulnerable act. Example: Openly sharing mental health issues such as dealing with a loss.

Reaching out and asking for help
Asking for assistance, help or guidance when you need it is a form of vulnerability. It could involve reaching out when you have a need to be listened to, seeking help to solve a problem, or asking for advice or input on a challenge you are working on.

Sources of inspiration:
bard.google.com
chat.openai.com
you.com