A few years ago I made a post about learning to play the recorder, and due to the magic and power of the link, I won't have to repeat myself here.
I have kept my recorder playing up (to a point) by playing in an early music consort (though I switch between recorder and viola d'amore, favoring the viola d'amore because of its ability to play parts that go beyond the ranges of the various recorders we use). I have devoted the past few (well, seventeen) years to the violin and the viola, and haven't actually practiced the recorder during most of that time.
I have the great fortune to be performing a piece by George Hunter for recorder, viola d'amore, and viola at the upcoming viola d'amore congress that is taking place in Evanston, Illinois this June. I'm playing the recorder part. The recorder part of the piece is not particularly difficult, so I have been spending a nice chunk each day practicing recorder music that is difficult, just because I can.
It is a hoot to switch back and forth from alto recorder to viola d'amore (using three clefs, sometimes). Perhaps I enjoy it so much because my brain has to engage itself so differently to play those two instruments from the way it engages when I play either violin or viola. After about a month of this mishegas, I can honestly say that I have no idea how it is that I remember where to put my arms, hands, tongue, and fingers on any given instrument at any given time, but I have made considerable improvement on all four instruments.
I teach people to play and to read music, but beyond the doorway I have very little idea how anyone remembers how to do anything. It is like remembering how to walk, or eat, or talk, or sleep.