Hello. 1. Recommended. Choose
moisturizer soluble in water. Most will be less gooey.
moisturizer oil-soluble type And choose to use at a low rate. 2. Same as krittin123 members. 3. Depending on the base, how many % of the composition of the formula? If more than 80% of the formula can be avoided.
สารกันเสีย can be added, but if lower than that I may choose to fill
สารกันเสีย a little more (0.1-0.3%) 4. The pH value is approximately 6-7.