I was always intrigued by the idea of using a vitamin C serum and by all the positive reviews of products like this. I began searching for recipes and found one that had three ingredients: water, Ascorbic Acid powder and vegetable glycerin. I tried it and the result was a rich Vitamin C serum that I used for a few days in the beginning, until I noticed that one of the ingredients was causing me breakouts. I found out that the responsabile was glycerin so I stopped adding it to my serum and instead use it for my hair.

Now I use only use two ingredients to make my own serum. Well, it's not quite a serum now, it's more like a vitamin C toner, ha ha. So I've been trying this recipe for the past few months and it's been really good so far. It's like 'my own' recipe and it's really efficient and totally inexpensive! All you need is water (preferably distilled), Ascorbic Acid powder and that's it. Below you can find the variations and I personally recommend starting with the weakest one, just to make sure your skin doesn't have a shock when you first use it. I copied the indications from this youtube video (where you can find detailed instructions on how to make your own vitamin C serum).

5% Serum 1/4 tsp. powder 4 tsp. distilled water 3/4 tsp. glycerin
10% Serum 1/4 tsp. powder 2 tsp. distilled water 1/4 tsp. glycerin
15% Serum 3/8 tsp. powder 2 tsp. distilled water 1/8 tsp. glycerin20 % Serum 1/4 tsp. powder 3/4 tsp distilled water 1/4 tsp. glycerin 

So as I was saying, I decided to remove the glycerin from my serum and this is my conclusion. Firstly, I started with 5% serum and after a few weeks moved up to 10%. I'm still on that 10% and I'm very comfortable. I don't feel the need to go further. I personally apply it with a cotton pad, as I apply my rose water toner. I use it let's say...5-6 times a week, only at night. I don't know if it's ok to use it so much, but it didn't harm my skin so far. You can apply a moisturizer after the serum, I don't always do that. I want my skin to breathe at least when I'm asleep. So far I noticed that my skin complexion is brighter, I have very few pimples and mostly when I don't use the serum (I tried not using it for 3 days) and it helped with my oily T zone. Since I started using this serum, I don't feel the need to apply a powder on my T zone and it doesn't get oily as much as it used to. I also don't wear not even a single drop of foundation since I started using this. I make a new batch every week so the product  is always fresh and good to use. I keep it a an old serum bottle, away from the light, in a drawer. When the serum gets yellow, you know that you can't use it anymore so be careful. I am no expert on this, so be careful when making any decision. You are the only one that knows your face and how it reacts.
I personally am really happy with this homemade product and will continue to use it. You can see how my face looks now (I wear nothing, not even moisturizer). I couldn't be happier with the results but don't get too excited and 'read' your face. If you'll give this a go, please return and share your thoughts!