Select Mesh -> Edit mode -> Mesh -> Clean Up -> Merge By Distance. (or just F3 -> and search for Merge By Distance)
Remove un-useful vertex groups:
Rigging is when you make a skeleton (rig) for the model.
Before you begin the rigging in Blender:
Select Mesh -> Edit mode -> Mesh -> Clean Up -> Merge By Distance. (or just F3 -> and search for Merge By Distance)
Remove un-useful vertex groups:
Any model with this skeleton should be compatible with our body tracking. It is required that the structure and names of bones are as described. One exception - you can use any prefixes in bone names, like for example "mixamo:LeftUpLeg" or "prefix_LeftArm". Parsing of the skeleton is case insensitive, for example, LeftArm bone may have any name ending with "LeftArm", "leftArm", or "leftarm".
Compatibility
This armature/skeleton is standard and default for game engines (Godot, Unreal, Unity), tools (Mixamo, Lens Studio), avatar systems (Ready Player Me), etc. For example any Ready Player Me avatar is compatible with our body tracking out-of-the-box. You can also use these avatars as starting point for your own character or outfit model.
In general, preparation of models for body tracking is the same as any other 3D model and you can use any 3D tool you prefer: Blender, Maya, Cinema4D, etc. The Geenee Avatar structure is compatible with Snapchat Pose Recognition with only difference in file format export (we use .glb). Any video you can find in Youtube could help you with manual and precise avatar rigging. The main difference is that final model should be skinned. See here for skinning options.