1. Meshsmooth only the selected faces by un-checking the 'apply to entire mesh' box in the options.
2. If you use Non-uniform scaling (scaling in less than all 3 axes at the same time) on a model it will cause distortion problems when animating, however non-uniform scaling within a sub-object mode will not cause the same problems.
3. When in Edit Poly or Mesh, hitting 1,2,3,4 etc will cycle through the sub-object selections, and when in edit poly hiting 6 will take you out of the subobject mode. Also, Ctrl + B will cycle in/out of sub object mode.
4. Alt+X = See-though or X-Ray mode
5. To rotate around a particular vertex, select your object (or set of sub-objects) lock the selection, choose either or from the drop down list, turn on vertex snap and rotate it all by clicking on the vertex you wish as the pivot. (CLICK HERE for more tips and trick free 3d models all3dmodel.com)
6. When in sub-poly mode, creating your own keyboard shortcuts can save oodles of time. Rather than scrolling up and down looking for "connect" and "target weld". Just assign "ALT-C" and "ALT-W" for example.
7.When modelling things at odd angles, (ie, arms, hands, feet etc) it helps to create an instance of the object, straighten it out and work on that instead.
8. Pressing + and - changes the size of the transform gizmo.
9. A sub-object selection in Edit Poly can be transfered over to another one by holding down Ctrl and clicking another mode button in the modifiy panel selection rollout. This is particularly good for the 'Ring' and 'Loop' commands in edge mode of edit poly.
Alternatively selecting the edges/verts .etc around and area (in effect, selecting a perimeter) and holding Shift whilst clicking a different selection mode will transfer over only the parts within the perimeter of the original selection.
10. The FFD modifier is a good tool for deforming meshes, its can be applied to a single mesh or multiple meshes simultaneously.
11. In later versions of max, hitting Ctrl+Backspace will remove both the edge and the vertex when in edge subobject mode.
12.Holding down CTRL when creating a a sphere, cylinder, teapot, etc. will allow you to rotate as you create. Holdings down CTRL when creating a box, pyramid, plane, etc. will create an object with even length/width.
13. When modeling wrinkles, folds, etc, on a curved surface, instead of moving your row of edges on 1 axis, convert the selection to Vertex (Ctrl + Click Vertex button under the stack) and switch your coordinate system to Local. Now, moving the slection on the Z axis will move them perpendicularly to the surface.
Alternatively you can use the 'Normal' constraint found in the edit poly modify panel for the same effect although this is only in later versions of max.
14. Modifiers such as Push and Noise can be applied to a soft selection on the previous modifier so their 'strength' varies accordingly.
15. To stop an object turning grey when freezing it, uncheck the 'show frozen in grey' in the object's porperties window.
16. Some spinner values that are limited can have that limitation overridden. But ONLY if they are animatable. Create a key in Track View for that parameter and edit its value there.
Now you can Relax by a negative amount or Spherify more than 100%.