You can scale selected objects by using either the resize and rotate handles or the Action Bar.
Using the resize or rotation handles
To scale an object by using resize or rotation handles
Select one or more objects, groups, or individual anchor points on one or more objects.
Notice that resize handles appear around each object.
Drag a side or corner handle to scale the object. You can use one of the following methods:
Maintain the height and width proportions by holding down the SHIFT key when you drag the handle.
Scale around the point of transformation (by default, the center point of the bounding box) by holding down the ALT key when you drag the handle.
The original large shape being scaled down by dragging a corner handle
When the same object is scaled up with the ALT key held down, the object scales around the point of transformation (in this case the center point)
You can both scale and duplicate a selection at the same time by holding down CTRL+ALT when you drag a handle.
Using the Action Bar
You can also scale an object by using the Action Bar.
To scale an object by using the Action Bar
On the left side of the Action Bar, click the registration point icon to indicate which part of the selected object you want to stay stationary during scaling. For example, if you want the lower-left corner of your object to remain in position when the rest of the object scales, click the lower-left corner of the registration point icon.
Adjust the W and H (width and height) sliders by dragging up or to the right to increase the value, or down or to the left to reduce the value, or click the field to type a numeric value. If you want to scale by a specific percentage, on the Transform options list, click Scale as Percentage.
Scaling by percentage in the Action Bar