For those of us who are introverted, or have lifestyles where we spend all day not talking to people except by typing online or having an occasional work conference call, it can be a "good deed’ to engage somebody in a conversation. Like, the other night I chatted for 5 minutes with a convenience store clerk I’ve been seeing off and on in the same store for about 4 years. I like her and she’s always a very good clerk and also kind of a fixture given that many of the other staff have come and gone, also this particular store is near a nursing home where my mother spent many months and now her friend will likely spend what’s left of her life, so it’s really nice to see a friendly face because I’ve often been stressed when going to that store. But it took effort for me to strike up that conversation, because I don’t talk to people, and in fact now that the store has a self checkout option which allows me to skip the long line, I can do all my business in that store with even less talking.
For my part, I probably wouldn’t consider an online donation to be a “good deed” given that I make them all the time. I also probably wouldn’t consider doing a prayer or indulgence for someone to be a major “good deed” because I do those all the time too. The idea is to pick something unusual and out of your normal comfort zone.