Open your VTuber avatar project in your modeling or avatar software
Import or create the outfit model
Fit the outfit to the avatar body
Adjust the outfit mesh to match the avatar proportions
Weight paint the outfit to the avatar skeleton
Test the outfit with body movements and animations
Fix clipping, stretching, or gaps
Add textures, colors, and materials
Save and export the updated avatar
Load the avatar into your VTuber app and verify the outfit appears correctly