This first tip is about how to use a shortcut to add and modify the Subdivisions in the SubSurf modifier.
- Press Ctrl+(Number) to add a Subdivision Surface modifier when an object (or a group of objects) is selected.
- The number you press determines the subdivision level.
- If the object already has a Subdivision Surface modifier added, pressing Ctrl+(Number) will change the subdivisions level.
Example: Select an object and press Ctrl+2; this will add a Subdivision Surface modifier to that object set in 2 subdivision levels. After that, selecting that object and pressing Ctrl+1 will switch subdivision levels to 1.