umm. . .I'm sure theres a tut around here somewhere. You know where it has the "render active view" button? well next to it should be a "render to picture viewer" and a "render settings" button. Click the render settings button and change the antialiasing to best to begin with, instead of geometry, then go to the "output" tab and choose the dimensions, then go to the "save" tab if i remember correctly and make the format a .tga and check the box that says "alpha channel" and then click the "render to picture viewer" button. Once it finishes rendering hit file then save and save it where you want it. In photoshop if you want to get the render alone take the magic wand tool and right click then click "load selection" then do "alpha path" or something and it should select the render.
If you want help...
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