Spread some buttercream on the cake board.
Place one layer of cake on a cake board and place in fridge for 5-10 minutes. This will help the cake stick to the cake board and not slip as you stack and frost.
Remove from fridge.
Top with approximately 1/3 cup of frosting and spread evenly
Repeat with remaining layers and apply a thin coat of frosting all over the cake for the crumb coat. Chill for 20mins.
Frost and smooth the sides.
Mark two vertical line on one side of the cake with a cake scraper or butter knife. This will mark the fault line.
Place cake in fridge for 20-30 minutes.
In the meantime, separate your small and large sprinkles.
Place approximately 2 tbsp of water in a bowl.
Remove cake from the fridge.
Dip the tips of your fingers in water before dipping them in the sprinkles. Stick small sprinkles into the fault line. Repeat until you have gone around the whole cake. Make sure to leave room for the larger sprinkles.
Fill a piping bag with frosting and pipe frosting above and below the fault line.
Scrape and Smooth with a bench scraper or offset spatula.
Once you’re happy with the look, place the larger sprinkles on the fault line.
Place cake in the fridge for another 20-30 minutes.
Pain the edges of the fault line with edible paint.