Basic Shopping List:
1. Resin (Castin Craft)
2. Mold
3. Mold Release (Castin Craft)
4. Resin Dye (Castin Craft)
5. Popsicle Sticks
6. 1oz Measuring Cups with measurement lines (Disposable, you can't really reuse these)
7. Gloves
8. Mod Podge (To seal pictures, images, or items)
9. Stuff to embed (Stickers, glitter, pictures, trinkets, etc.)
10. A large bowl to cover your mold while it cures so no dust or hair gets in it.
11. Something to cover your work surface (DO NOT USE NEWSPAPER OR PAPER TOWELS!) Use something plastic so the resin won't leak through it and ruin your work surface. I ♥ those plastic cutting mats you get at the dollar store, they come 2 in a pack and are reusable but disposable if needed.
12. Something to hold your mold level if it's an odd shape that doesn't sit flat.
13. Resin Spray or thick gloss (totally optional) if your piece doesn't come out glossy or has pits you can give it a quick spray or brush on a coat to finish it off.
Castin Craft is the leader in "hobby" resin casting. You can find them in Hobby Lobby or Michaels, all the resin supplies are in once place and usually it's only a small part of a shelf, you may have to hunt for it or ask someone where it's located.
A 1:1 ratio resin is SOO much easier than trying to configure how many drops of a catalyst you'll need as it's going to change every...single...time. Your resin may not cure completely depending on size, thickness, dyes used, temperature, humidity, barometric pressure... *Ugh.*
You can use just about anything to dye your resin, but to get started Castin Craft offers a specific line of resin dyes in both opaque and transparent.
Once you get better you can search online for industrial resins - they're way cheaper per ounce, have better quality, are easier to work with, and don't have the potential to yellow; but you have to buy gallons at a time and shipping can get crazy since it's really heavy and considered a hazardous material, so yea - make sure it's a hobby you're REALLY interested in!