Just starting need recipes and instructions

I want to start soda making and want to get some good recipes using the yeast technique.

I'm not sure exactly how you're making the soda, but one flavor I'm totally hooked on is made with lemongrass simple syrup. I take a few stalks of lemongrass, cut them up into two inch chunks, then blend them in my Vitamix with a cup of water. Afterwards I add a cup of sugar and simmer the stuff for about 30 minutes. Then I pour it through a tea towel into a jar to filter out the grass, let cool, then store it in the fridge for soda making. I would experiment with it, mixing with a little selzer water (so you'll know what its like carbonated), until you have a good balance to your taste. Afterwards make it in a soda recipe you have.
I don't like adding anything other than the lemongrass SS and what's necessary for yeast-based carbonated soda.