Yeah, understanding the rhythm of Flamenco (compas) is probably the hardest part.
The 12 count is like counting out 1/4 notes. The closest thing to relating the 12 count to western music would be to divide the 12 count into 4 measures of 3. So your typical Solea would look:
|| F (1 2 3)| C ( 1 2 3)| F (1 2 3)| E7 (1 2 3)||
And that would be your typical solea song form.
In westen music the accent (or down beat) is always on 1, this is the main difference w/Flamenco, in the solea the accents are on 3 6 8 10 & 12. So if I took the above chord progression and put an asterisk next to the aceented beat it would look like this:
||F ( 1 2 3*)| C ( 1 2 3*)| F ( 1 2* 3)| E7 (1* 2 3*)||
So as you see this doesn't translate well into traditional western methods of dividing music into bar lines and such...so instead they hear everything as 1 12 bar phrase. So in Flamenco you would count:
||F ( 1 2 3*) C ( 4 5 6*) F ( 7 8* 9) E7 ( 10* 11 12*)||
Accented beats would typically be approached with a single down stroke. Unaccented beats ( 1 2 4 5 7 9 11) would recieve a rasguedo.