Sometimes you are going to get screwups. it is called learning.
Here is something I do when trying something new or unfamiliar. Keep careful notes, detailing everything you can think of that may affect the paint. Temperature, time of day, humidity, application techniques, surface prep techniques, everything that may affect the paint. Write down the results. You will eventually end up with log book of what works, and what does not.
Do not forget to follow the directions in the paint product lead sheet as much as possible. The local store you buy the paint at may also have some good advise for you.