These are pretty easy and fun to make. Because there were a few, i didn't take in progress pictures of all of them.
I bought a package of "glass bubbles" (i don't know what else to call them or what their real name is) a long time ago and just ran across them recently, so i forget how much a pack costs, but they can be found at craft stores.
For the sun magnet, I painted on the yellow sun first (using the plastic pointy end of a paint brush) then let it full dry (it's important to let it fully dry or the next layer will bleed into it/over it). After it was dry, I painted on the blue background and let it dry before using craft glue to glue the round magnet on (also purchased at a craft store)
While I was making these magnets, I was wandering around my kitchen waiting for these to dry and saw my roommate's giant basket of straws and had an idea
For the "abstract-ish" looking one, I dipped the tip of a straw in the color paint I wanted then just dabbed it in different places over the paper. Then, switched colors (and this time i didn't wait for the colors to dry before adding a new one)
Then, I placed the glass bubble over the paper (once it was all dry) and traced around it, cut around it, then glued it to the back of the glass bubble using mod podge.
For this one, I used again the pointy plastic end of the paint brush to do the purple lines and blue dots. Once it was fully dry, I painted on the yellow background.
My roommate is a giant packers fan, so I thought i'd make her a little magnet
when doing letters, don't forget to write them backward! I did the green paint, let it dry, then did the yellow background.
The important thing for all of these is to do a layer, let it dry, then do the next layer.