You'll definitely want to use it on your face, but start out slowly because this stuff will really buff away the top layer of dead skin, and you don't want to be too rough. Although, since I've been using baking soda on my face and body for years, my skin has been strengthened and can take very aggressive exfoliation.
What's revealed will be soft, glowing new skin. "Soft as a baby's bottom," as the saying goes.
All you do is pour out a small handful of baking soda, add a little water to make a paste, and then apply in gentle circular motions. I recently suggested this to my sister, and her teenage son noticed her skin was luminous after just three days... and, if you know anything about teenage boys, they're not too observant, at least not about the condition of their mother's skin.
I've had strangers see me from across the room and rush over to compliment my skin. This is no small thing - people will notice!
I also use baking soda on my neck, chest, and breasts. It can also be used on your arms and legs, to not only make your skin smooth, but to strengthen it and firm it up... and who doesn't want firmer upper arms and thighs?
I keep my baking soda in a pretty container with a screw on lid in my shower and fill it up every week or so. But when I'm in a rush and washing my face in the sink, I use a quicker and less messy method. Then I use my trusty Buff Puff. It's a rough sponge that exfoliates just as the baking soda does, and it comes in three variations: Extra Gentle, Gentle, and Regular, and costs about five bucks. Just wet the sponge, add your favorite facial cleanser, and use the same gentle circular motions. You will probably have to stick with just your face at first, if you do decide to try it on your neck, use an extra soft touch since the skin on the neck is much more delicate than that of the face.
So there you have it, my two favorite anti-aging exfoliants. There are many more on the market, some with much larger price tags, but I really do believe these are the two best things you can use to get that dewy youthful glow.