Before drawing in isometric or axonometric view, use the CADguides and CADisometric palette to set up your grids and view angles.

CADguides - Isometric view
Choose Window > CADtools > Show CADguides to open the CADguides palette. If you want to view isometric grids in the background, check Show grid and choose Isometric from the Lines popup menu. If you want to snap to grids, check Snap to grid and set the snapping tolerance.

CADisometric palette
Choose Window > CADtools > Show CADisometric to open the CADisometric palette. The top left cube icon represents the current isometric view. To change the view, click and drag on the cube icon. Make sure the icon is free to rotate by unlocking it - click on the unlock button until it appears unlocked. The grids will follow the changes in the view.