This is a step-by-step guide on setting up your grab points
After creating a grabbable object, your objects hierarchy should look something like this:
Grabbable hierarchy with grab points
As you might've noticed, the grabbable has kindly provided us with two grab points. Open one of them and let's see what's up.
Grab point in the inspector
Clicking on preview pose will instantiate a preview hand and focus on our grab point, disabling the selection of all other gameobject's.
Grab point and the instantiated preview hand
Simply adjust the position and rotation of the grab point by manipulating its transform in the editor or using the scene positional and rotational gizmos.
This is enough if you want to create an object with just grab points and no hand posing.