I think everyone on here could tell you that testing never goes away. When I first started candle making, it was all I did...even now, as I not too recently started up again, I am still testing....testing scents, testing styles, test test test. Keep good notes. Fragrances are truly trial and error. Suppliers offer sample sizes, making it a bit easier to compare the same scent from multiple suppliers. For example, you buy 3 different vanilla's from 3 different suppliers. You make 3 different candles (label them as to wax, wick size and amount of f.o. used and scent supplier) Then, burn em. Take notes (I have to, because I forget a lot)...is it a true scent? does it have a chemical smell? does it have a weak or strong cold throw? how long before you can smell it once it is lit? does it burn clean? You get the idea. HTH