How to cast resin
Resin casting is much like silicone, albeit with a few less steps.
WEAR GLOVES. Uncured resin is a toxic substance!
1. Measure and mix your resin amount. We find it helpful (with small models) to pour amounts of resin and hardener into the extra small plastic cups, then pour to the larger silicone, as it can be hard to judge small amounts against the larger denominations on the cup. Mix your resin in a silicone cup! it makes for easier cleanup as it will peel right off, whereas it will cure onto the plastic.
This resin is a simple 1:1 ratio of resin to hardener, which mean you'll use the exact same amount of each.
If you're not sure how much resin to use, try the handy water trick! put a little water into one of the measuring cups, note how full it is, and then put your original models into the water. Take the level of the now displaced water-- subtract the original and you'll have the mass of resin needed.
(You'll want to make a little extra, so don't overthink it, but don't be excessive.)
2. Add color or inserts (if desired)
Alcohol inks (pictured) can be added to the resin to color it. Squeeze a few drops at a time, and check how the color is progressing. If you're using multiple hues, mix thoroughly to have a uniform color, or simply let the pouring mix your colors into translucent swirls.
If you're adventurous, you can actually put things inside your resin! Make sure they're small enough, and give then a quick swirl in the resin beforehand to help fill in gaps, and arrange it as desired inside your mold! Common things include colorful foils, dried plants, small charms, etc.
3. Pour your resin
Go slow and careful! fill your mold to the top, then give it a minute for some bubbles to work out, and overfill a small amount. (This is why the base is so important-- it will catch spills)
It's always better to overfill than not-- It's much easier to sand or cut off excess than it is to try and add a corner.
4. Get it to the pressure pot and cure!
Make sure it's got a basin!