Hi! Bre here. I have been using African black soap for years. I don't have acne-prone skin but my skin is sensitive. I started using black soap to help clear up the irritation and breakout issue I had from other cosmetic products and....IT WORKED! As far as acne...I can't say for sure but you can always try.
The way I use it is :
1. I wet my face first
2. I break a small piece off, lather it up under the water on my hands to get a foam like texture
3. I put the small piece of soap back in the container then just work in the foamy soap on face then rinse
This soap lasts forever and its cheap. I usually buy it from my local beauty supply store...its like $3 for a medium sized bar. I've also seen it in Walmart.
I hope that this helped and let me know how things work out!