I started with the cadence that I found from somewhere on the internet. Then I adjusted the timing to what felt good to me.
I found that https://github.com/grocy/grocy worked well for me to setup these kinds of things as chores. I guess that a callender would work too. I just like to have everything on one page.
My first thought was the same thing. But then I realized that birthday cards go in envelopes. Usually they go through USPS, not FedEx.