question on DIY C02

i dont do it by cups.. So just fill up the 2L bottle to the point where it starts to curve on top. Then pour the sugar try using 1.5 cups first since this is your first mixture. Then close the bottle and mix it very good until no sugar grains are seen. Then pour out some of the mixture into a cup and put 1/4-1/2 teaspoons of yeast and mix it. Let it sit in the cup for 15-20 min to hydrate. then pour the sugar/yeast mix back into the bottle. Mix again and wait until it starts bubbling.
 
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