D
EDIT: You changed it. The current version is good.
Sorry, @FediTips , but your suggestion on what to do with your first vote is, I believe, the worst hint from you I've read thus far. With margin. (Which is to say I usually like what I read from you.)
A first vote for a party that has a tiny followership in your voting district and no reasonable chance to win that district is basically wasted, from an election-outcome point of view.
To use your German federal parliamentary election votes to maximize your influence on who gets into parliament:
First vote: Which candidate is likely to win in your particular local voting district? If you like that person, vote for her or him. If not, vote for the person with second best chance.
Second vote: Which parties have a reasonable chance to get into the next parliament? Choose among those.
Deviations from this send political signals, but influence outcome less.