First, I would say that cake decorating is an art and someone with a good hand could do it free-handed, but one thing that you could do is use a cookie cutter to outline the shapes that you want and then just fill in with colors.
i'm going to guess either a FBCT (tho it looks too clean for that), a piping gel transfer, or a "hole poke" transfer (where you trace an image on paper by poking holes and then pressing it onto the cake). i can't freehand, either, but those 3 methods are what i usually use to make an exact copy of something on a cake.
ETA: i'm only saying transfer methods be/c i know that that cake is based on a popular first birthday plates/decoration theme.
Thank you so much. So if one does the transfer either via piping gel or poking holes with toothpick. How do they fill it in? Do they smooth it out with pointed spatula?
i fill with an appropriately sized round tip (e.g. 12 for larger areas, 3 or 4 for smaller areas). to smooth, i usually just use a regular spatula, unless it's a really fine corner, then i use a tapered one, yes.
I would use my overhead projector to do this. I HATE tracing.
I think the interiors are simply smoothed with a finger dipped in cornstarch. It's really not that smooth but is super cute.
you can also smooth it out with a damp paintbrush. I have done a toothpick transfer and it takes FOREVER! Just try to free hand on a practice board, you'll be surprised!
My immediate thought when I saw the picture before I even read the other postings was using cookie cutters. In fact I have a Wilton Butterfly, flower, leaves cutters that I'm confident are this size. Also, the butterfly, lowers and leaves look raised like they were cut out from fondant and then laid on the cake with piping to bring it to 'life'. That the route I would go as I'm not good at free hand.