I'm no master but I always add some white then the yellow to get it to stand out. Lots of the time I take a paper plate or or a small zip lock bag and then add 2-4 drops of white then start adding my yellow or any other color I'm working on mix it up good with tooth pick or pop sickle stick. To me it's a lot cheaper to waste a little color than it is to make a batch of plastic and each time trying to find the right color. There are lots of great plastic bait makers here for sure they all have great ideas and knowledge