First color your beads by placing beads in plastic sandwich bags and add drops of food coloring inside. Then rub the beads to absorb the colors and leave them in the bag until all the colors are absorbed. You get vibrant colors that way and can “paint” a lot of beads all at once.
Decide where you want your rainbows on the wooden block and puncture holes in the right places with anything sharp.
First start threading a pipe cleaner in a rainbow pattern!
Similarly, repeat for the other one.
When you’re done you have a beautiful beaded toy to look at that’s a colorful display. You can always unthread and start over again to make as many rainbows as you’d like!