I suggest starting with a 3ml batch with low flavor %. Super Concentrated I start at 2%, Concentrated I start at 4%
Heavy shake, heat soak (steaming tap water in a bowl, I let the bottle sit 10-15mins) Heavy shake, sit 12 hrs, heavy shake and test. YMMV
I do my test batches with NIC, many suggest saving money by testing without NIC, for me the NIC changes it enough to alter taste. YMMV
Not trying to dodge the details, it really is to YOUR taste. You can add .25% flavor, test again (this does dilute the NIC strength). REMEMBER how much you add. My greatest creations I can't reproduce because I DIDN'T keep track of what I added.
Good Luck!
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