you want to add warm water, the amount of sugar, yeast and baking soda will depend on your bottle size. I use 2 liter Mt Dew bottle. I fill the sugar up to where the bottom of the label would be. Add .5 tsp of yeast, .5 tsp of baking soda and fill it with warm water 3/4 up.
I add the sugar and water. Cap it and shake until the sugar has dissolved completely. I then add the yeast and baking soda. Hook it up and give it a good shake. I've got co2 bubbles in less than 2 hours. I have 2, 2 liters going at one time into a gatorade sump bottle.
It took me awhile to get my mixture down. Anything more than .5 tsp of baking soda and my production doesn't last all that long. Less than .5 tsp and I get zero co2. You will just have to play with your numbers until you find what works best.