I've been using natural deodorants for about 4 years, after really learning the dangers of antiperspirants.  I'm not really a sweaty girl, nor a stinky girl, but I do need something to keep the moisture and odour at bay. I've used my fair share of healthier store bought deodorants, they all work for a while, then stop. I've tried the salt crystal, but loose interest very quickly. I've been using baking soda & oil since last summer off and on. Every time I stop, I become frustrated with the breakthrough smell of natural deodorants. I find they cover for half the day, then my natural odour comes through and mixes with the smell of the deodorant creating a not-so-pleasant smell. My natural smell would be better than that mixed crap. 

Here is my recipe for perfectly wonderful (cheap) and easy deodorant. If you are sceptical, you can use your regular deodorant as the oil base to start and slowly wean onto just oil. 

-Oil of choice; almond, olive, vegetable, coconut etc 
I use a combination of olive oil and coconut oil in a small pump container. It is more work than worth it though, because I need to heat the coconut oil in the container before using it. Next time, I'll use coconut oil in a small lid container or vegetable oil in the pump. 
-Drop or two of essential oil of your choice, if you'd prefer a smell to your deodorant 
-Baking soda (sodium bicarbonate) 

After my shower, I pat my armpits dry and add a small amount of oil to them. I then pat on a small amount of baking soda. You really only need a small amount. Done! 

You can also make a wet deodorant if you'd like. Mix the above ingredients into a small reusable container with a lid, and apply as needed. I find the dry version with oil first really helps it stay on all day, and keeps me dryer than the wet version. 

I've read that some people skip the oil and just use water directly after the shower. I've tried this, and I find it doesn't last all day or make my armpits as soft. I also find the feeling of putting on the baking soda with just water more abrasive than the oil. Personal preference though. 

I'm not sure if it makes a difference, but I have lovely bushy armpits. Some women (and men) find they smell more with hair, I find I smell way less. The baking soda stays in place better ;) 

Baking soda as deodorant works through high-stress environments for me, hours and hours of labours (forgot at my last birth, big mistake), synthetic t-shirts, and normal sweat. It is very amazing and totally worth a try, since you probably have everything in your house to get started right away. 

Using baking soda as shampoo, my entry here.