Resources for Fluency with Pandas?

I'm bringing this up now because I've talked to other people who have the same problem.

When I have a question about python I know how to look up the answer quickly in the manual.

With pandas I am not so fluent and find myself using Google or Stackoverflow to look for answers which I think is a source of errors and waste of time. Also I work sporadically with pandas so once I get one data analysis project done I don't really consolidate the experience and come back feeling like a fresher a few months later.

Architecturally I don't find Pandas strange, that is, I understand the benefits of column oriented processing (and learned that people who fund data analysis startups don't want to fund anything else,) so it's not strange to me that you're supposed to build a dataframe a column at a time as opposed to row at a time. Still, I find that the "pandas way" of doing things doesn't really stick in my mind.

Probably reading the manual, then reading the manual again, and again, over a long period of time would help, but I'm wondering if there is a really good set of problem sets (like Hackerrank) that will help develop fluency in pandas, or alternately, a really good "cheat sheet."