Chill the cake layers (and frosting) for easier spreading
Level the cake layers if needed
Place one layer on a cake board or plate
Add a thin layer of frosting on top of the first layer
Stack remaining layers, pressing gently to align
Apply a crumb coat: spread a thin, even layer of frosting over the entire cake
Chill 15–30 minutes until the crumb coat firms up
Apply the final frosting layer, starting on the top and working down the sides
Use a bench scraper or offset spatula to smooth the sides
For clean edges, wipe the scraper/spatula between passes
Smooth the top with a flat spatula, rotating the turntable as you go
If desired, create swirls, rosettes, or ridges with a piping bag and tip
For a piped border, fill a piping bag, pipe around the top edge, then smooth lightly if needed
Clean up the base edge by wiping the plate/board with a damp towel or paper towel
Chill the finished cake briefly to set the frosting before serving or transporting