- The Sims uses triangles for meshes and will not accept anything else ( I have exported meshes with TS1-Blender-IO without triangulating the mesh, so I believe it will triangulate meshes for you when exporting. )

- Be kind to computer performance, keep the polycount low. Especially if you intend to share the mesh with others.

- Make sure the normals of the mesh are facing the right direction, or your mesh will appear inside-out when in-game ( you can perhaps take advantage of this to create interesting effects. )

- Mesh objects must be contained within a collection folder and follow this naming guideline: xskin-[collection name]-[base bone]-[body part]

- Every vertex must be assigned to a vertex group, but can only be assigned to a maximum of two vertex groups. The Sims will not accept vertices assigned to more than 2 groups.

- A custom string property must be created to designate the base bone the mesh will be assigned to. Custom properties can be found in the Data tab within the Properties editor while the mesh is selected. In the Data tab, go to the Custom Properties section, and click on “New.” You will have a new custom property, select the gear icon to open a panel. This panel will allow you to edit the custom property. Change the type to “String,” then add “Bone Name” to the property name entry, you can add “PELVIS” ( or whatever you want the base bone to be ) to the value entry but doesn’t seem to work when submitting changes, so change it after selecting “OK.” If the value next to Bone Name is "1.0" or anything that is not the name of the base bone, then change it to the name of the base bone.

- If your mesh has vertex groups for multiple bones, then use "PELVIS" as the base bone. If the mesh has only one vertex group, use whatever bone the vertices of your mesh is assigned to.