To use the Geo Fastcloth system:

1. Go to File\Append\

2. Select the GEO_FASTCLOTH.blend file

3. Navigate to the Node Tree Category and select the GEO FASTCLOTH node tree.

Note: instead of Appending in the node tree you can Link it into your file (same process). This way all the settings remain in one master file, rather than in the individual files you apply it to.

4. Select the object you wish to apply Geo Fastcloth to. Object should already have some deformation modifier like Armature, Surface Deform, Hook, etc.

5. Add a Geonodes Modifier and select the GEO FASTCLOTH node tree.

6. If your objects or their parents/armature are scaled to something other than 1.0, enter that scale in the "Scale Correction" input. For instance Mixamo armatures usually have to be scaled down to match Blender units.

7. Choose 1 or 2 collider objects. Or if you need more objects to act as colliders, choose a collection from your Blend file.

8. Adjust the settings as you see fit.