Please tell me a treatment that makes my skin glow.

There are days when my face looks particularly dull whenever I take a picture. When I look at celebrities, I get jealous because their skin glows.
Lately, I've been envious of that, so I've been researching various ways to achieve radiant skin. I've been trying everything from moisturizing packs and vitamin C products to exfoliating, but it only lasts for a short time, and after a few days, my skin feels dull again... It seems like they say that a radiance that comes from within is truly different, and I think it's true. Does anyone have any glowing skin care methods that have actually proven effective? Or, if you know of any glowing skin treatments, please let me know!