How To Be "helpful" And "giving" Being An Introvert?

I would not exactly classify myself as an introvert but more of an ambivert which is not easy either
I always draw a boundary and never get close to anyone not that I do not want to but I think it is better this way for me and others.

However..I want to be helpful and giving which I truly believe is a great way to live life to the fullest.
I can never be one of those openly helpful and amazing extroverts who do a lot.Still I would like to do my part to help people even if it is subtle.

Some of the things I do..

1)I make sure to donate clothes and toys.
2)I live a simple and minimalistic lifestyle these days and I do not waste stuff.Don't know how this helps others but emotionally I feel fulfilled and feel positive.
3)I always make sure to donate some amount after we buy.Usually,we do grocery and in billing section,we are asked to donate some amount if we can?I make sure to do that.
4) I try my atmost to be intentionally kind to people and make sure to atleast give a smile when I see someone face to face.It actually brightens up their face.
5)I am kinder to my family though they have treated me wrong coz I feel everyone is growing older and its time to let go.
6)I am nicer to my neighbors and more inviting with the neighborhood kids which is a huge deal for me coz I used to have a lot of social anxiety problems and still do but I try.the kids actually like me and feel comfortable at my place
7) I helped a friend lose weight and she looks so happy.
8) I try to donate money on my birthday,anniversaries instead of getting gifts for myself. Infact,I stopped buying more than even neccessary and trying to spend to people who needs it.

what more ways I can help others without being openly expressive?