Hiya! I am in publishing and have designed lots of mags. Plan Plan Plan first.
Make sure you have a couple of page templates. Depending on size, perhaps a 2,3 and 5 column. Get a main heading font, sub heading font and body font. Looks really cool if you have a break out article thats completely a different layout and a little crazy. Depends on kind of mag of course.
Make sure you speak with printer before you design the cover. If you want a spine (most of us do :p ) get your quote on paper stock/gsm and they can tell you spine width. If no spine they should still tell you cover size.
As for resources, just get yourself to your fave newsagent and pick up a mag you like or a design mag with tips or a book on typography.
Good luck! would love to see it. I love mags.
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