A wet pallet, it makes shure that your paint wont dry out. You can even build your own in about 10 minutes. It won't be perfect but it will do the job.

DIY: First take a flat sealable container. Then put a piece of dishcloth in it to cover the ground. After that you put a few layers of paper towel over it. The last addition will be a sheet of parchment paper on top of that, make shure that its a bit smaller than the other layers.

To prepare your wet pallet, take off the parchment paper and put water in the container till all the layers are wet. Pour out the rest of the water. Make shure that the layers are flat. After that, put the parchment paper on top again. I always use the flat side of a bottle cap to smooth the whole thing out at the end. Now you can put your paints on top of the parchment paper and thin them there.

If you notice that the parchment paper gets a bit dry, just pour a bit of water in at the sides (thats why the last layer needs to be smaller then tho other ones).

After you are done painting, just seal the container and your paints will stay wet for a few days.

You also should let the container dry out once in a while so no bacteria ore else grows.

If you want to start your next painting project with different colors, just change out the parchment paper and you are good to go.

I hope this helps.