I think it's difficult to say what a "stoner" looks like. We used to be portrayed as lazy, unkept, and not terribly brite. I'm 6'2, 285, with a shaved head and full beard, also covered in tatoos (though a long sleeve shirt will cover them).
During my work day I look like what I am, a business owner, upper income, fiscaly conservative. I wear a jacket and often a tie ( but my ties might give it away a little, most are Garcia's )
Durring my off time, multi pocketed shorts, Hawaiian shirts, flip-flops, and occasionaly a derby.
My nieghbors think I'm a accentric gardener/Bar-b-quer (but most of them are middle-aged, middle management, boozers)
So I guess most of all, I really don't care if people think I look like a stoner, I just smile and go about my business and encourage others to do the same.