How to enlarge breasts in photoshop.

hmm, this may or may not be a good tutorial because she's wearing a t-shirt.

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Also, I was going for a more subtle look.

Huh i guess it might have been to subtle for me :P

Here is a not so subtle one. It's not nude so hopefully this won't break any rules but i will spoiler it just to be sure.
[spoiler][/spoiler]

Good job, but that's not even attractive to me. Looks like she plastered some balloons to her chest.