Many magical items either "look" magical (in their description) or have some other magical-ish property (glow, hum, etc.) If you avoid stuff that's "obviously" magical (charred bracers, for instance) and try to limit the glowing/humming stuff to a single glowing item that you know isn't magical (so you can see in the dark, if your class needs light to do so) then you should be fine. Or just find a rager and ask him to look you over.