When I first started learning to to create resin art, I learned by watching YouTube videos. This was a great starting point, but they often left out critical steps. It wasn't until I ruined a few large pieces of geode resin art that I had to research deeper as to why my art was becoming runny and yellow.
Here are a few tips I have learned about using resin over the years:
Make sure to mix the proper ratio that is labeled for the brand. Meaning if it is a 1 to 1 ratio, you must measure it based off that as close as possible. You can do this with a measuring cup or a scale.
Always mix the entire amount measured, including the bottom of your container. Use two containers if possible to keep transferring the resin to ensure you scoop all of the liquid out of the bottom.
You will know your mixture is fully combined when you no longer see streaks in the liquid. I explain this to the students in my resin art classes in Denver, "The mixture will start off looking like if you put oil inside of water. Once it is fully mixed it will look only like water."
Buy a good quality resin, and if you are doing art work, use art resin. A lot of resins at hardware stores are easily accessible, but I have found that they yellow quicker and they have more harmful chemicals compared to art resins.
These are the top tips for using resin as a beginner. These small steps will save you a lot of time and money when it comes to using resin!