Testers has nice starter kits that you can get at hobby lobby but colors are basic and no thinner is included . I use odorless mineral spirits
I got my son this two sets. The one in black case colors seem matte finish. My 12 years old son want to start kit bashing. So am slowly teaching him what I have read. Teaching that thin layers is what works better. Below is what he has done so far. I see some lines, but not sure if paint lines or figures wasn't clean properly. He also wants to learn how to dye the transformers. He wants to die tailgate red. So will see how it turns out. Thanks for your input.
that testors set is acrylic so if yu used mineral spirits it mightve caused the lines. acrylic can be thinned with acrylic thinner or water. i dont know about the other set it should tell you on the box what the base is. clean with oil tackling soap like down and warm water and brush it to a nice lather be careful not to let peoices fall in the drain. dying is much different from painting where you chemically change the color of the plastic and if you dont know what you are doing you can melt the figure so be careful