1. Get seeds from Seedos or make a Whirlm resident.

2. Make a home by going to Willy's shop.

3. Select one Whirlm to romance with the other Whirlm.

4. Romance the two 20 or 40 times.

5. There are now 42 Whirlms. Go to Lotties Shop and buy a few happy/joy sweets or go to Petulas shop and decorate most of the Pinatas you have with the cheapest accessories (if you're scarce on coins).

6. The Whirlms are full on candy. Go to the crate and press Y, select the ones with the accessories.

7. When all of the Whirlms are back and more valuable, sell them all and you'll get loads of coins!