First you bake a cake using any recipe you want, and crumble it up either by hand or in the food processor. Then you mix it with enough buttercream to make the mixture sticky enough to hold together but not too gooey, and use your hands or any cookie cutters or moulds to create whatever shapes you need.
You can then either dip them like this and get cake balls, or put them onto lollipop sticks to make cake pops! I had picked up a bag of orange Candy Melts from Hobbycraft to make pumpkins and then on the spur of the moment decided to also make Pac Man style ghosts using white chocolate. The orange Candy Melts were a bit of a disaster, after melting they were too thick and when I tried to dip a pumpkin it broke off the stick and fell into the bowl! So I resorted to swirling the coating on using a spatula, which did the job but I didn't get the smooth finish that I wanted. The ghosts were also tricky because they're not a round shape so can be a bit wobbly on their sticks - I managed to dip them into the melted white chocolate but a couple did hit the deck as well...
You can really get creative with how you decorate your pops, I used Angelica cut into small strips for the leaves on the pumpkins, and then mixed up a bit of black icing to pipe the faces. I love how happy and cute the ghosts are, didn't want to go too scary for a baby party!
Once the chocolate coating has dried you can lay the cake pops down in a box and they'll keep for up to a week in the fridge, the buttercream stops them from drying out as quickly as a normal cake - but good luck making them last that long because they are delicious!