You can easily resize the manipulator in the viewport
Open a scene with a character from the samples.
Select any controller
Hold Ctrl and right mouse button
Move the mouse to resize the manipulator
Mark stage complete
Moving with arrow keys
In some situations, it is convenient to use the arrows on the keyboard to move the selected objects. Note that moving this way works relative to the current camera view.
Select the point of the character's arm
Select the translate manipulator
Use the → ← ↓ ↑ keys to move the selected point.
Open the Scene settings \ Manipulators tab
Change the numbers in the Arrow step line to increase or decrease the distance when applying arrows