i still think that downloading a template (biggest you can fin) and messing arround with the codes to see the different effecs is a very good way to learn.
I never opened a book of html neither css and i think i am pretty good at it.
Designer ? which means designing stuff not coding if we want to use the correct definition of waht you ask... i think the best way is have art class

The only place i learned was in the USA, i lived one year there and i could of choose 2 different classes i wanted... so i just picked Art, and i admit you get to know lots of stuff, how to hold a pen for example.. yes might sound stupid but.. hey... Anyways after a year i was doing some pretty good stuff and i think thats where i boosted my designing skills... actually its where it started.
Learn art... history of art can help, color shemes is important i guess to have your colors match, also i believe that if you want to kick ass you need to listen what it is asked, especialy if you are working for a client. Make sure you understand what he needs... its important.
QUOTE
learn by yourself.. its the best way tbh.
In short, i totaly aree with iamandy, even tho the artistic skill needs some structur which you can learn best via a teacher aka at school.
Oh yea.. keep practice