I picked up my felt at Hobby Lobby:
1 sheet of stiff yellow (called easy felt, I think) $1.50
1 sheet teal $0.25
1 sheet dino $0.75
Total - $2.50
I chose a stiff yellow for the base to make sure the crown would stand up without being floppy. I cut a long strip with a point in the middle (like below). Then I tried it on Baby B's head and it was way too tall and looked goofy, so I cut the band a little shorter. It looks much better now, and I'm glad I checked the size before I went any further!
I tried out a couple ideas for the dino print before deciding on this. I just centered a piece on the front and cut it slightly smaller than the base so the yellow would show around it. I glued it down with Elmer's glue, but I'm sure sewing it down would look nicer. But I'm all about speed and ease!
I cut a "1" out of the yellow and played around with the teal to make it stand out more against the dino print. You can see in the top left corner an oval that I tried first but wasn't crazy about. I eventually ended up with an outline just slightly bigger than the 1 that I like liked. I glued those pieces down as well, and left it to dry. I took quite a bit of glue because the felt soaked it up so fast! Next year I'll probably try sewing it instead, but by this point I was committed. :)
The next picture shows two things. First, I used some extra teal to cover where the band will touch Baby B's head. The stiff yellow was a little scratchy, so I added a softer layer. Second, you can see where I attached another piece to the band to make it long enough to reach around Baby B's head. You may not need the extra length, but Baby B's head is off the charts! Now I just need to get the exact size figured out and get the two ends connected. :)