Rice Vinegar easily made at home

I've been interested in making vinegars lately. Not the cheap white vinegar, but vinegars more suitable for marinades and dressings. My boyfriend makes home made red wine and once this batch is done I will be making red wine vinegar.
But until then I am experimenting with Rice Vinegar. Not to be confused with Rice Wine Vinegar, simple Rice vinegar is made with just rice, water, sugar, and yeast.
I searched around online for recipes and some were varying. So I went for the middle ground, but also did some things a bit different.
I soaked the rice for 12 hours or so, in the fridge, covered.
Then I strained the rice out with cloth, and measured the murky water that resulted. I had close to 3 cups, so I added a bit of water to get exactly at 3.
Then I put it in a pot with 3/4 C sugar per 1 C water. Stir til sugar dissolves completely.
Cooked it 20 minutes over a double boiler~ one pot sitting on top another slightly smaller pot of boiling water is what I use, some people might actually have a double boiler, but I really don't know what that is.
Then I let it cool, but I let it cool for 8 hours because I left the house and didn't come back until later. My mixture was now at something like 4 cups because of the added sugar.
I added 1/4 TBS (almost 1 tsp) of yeast to the mixture and stirred well. Poured in a glass jar with a coffee filter on top secured with rubber band, the yeast can ferment the rice syrup and breath and release gas. Yuck! I set it in my closet in my house on a top shelf, since "heat rises"- even though my apartment is a steady 68degrees...
Going to bed I wondered if I should have heated the rice mixture a bit so it was warm to activate the yeast... So when I made green tea with breakfast this morning I set my glass jar close to the burner. Then with gloved hands I held if over the steal with the bottle just in the water, only for 30 seconds or so. If it gets too hot it will kill the yeast. I did that twice, with a break in between and set the container close to the burner after.
It appeared to work~ now there were little bubbles all in the container, whereas before there were just a few near the top. My Yeast is aliiiiive! It's Alliiivvee!

Happy Halloween