This page explains step-by-step how to make the mouse left-handed in Windows 7. By default, your mouse is set up for a right-handed person, with the primary button on the left. However, you can swap the function of the mouse buttons from the default left click, so that a right click is instead used for selection and dragging. You'll just need to remember to press the opposite button to what is called for when you are following instructions (for example, if you are requested to right-click on something).
Change the function of the mouse's left and right buttons
Step 1: Open the "Mouse Properties" window
Right-click anywhere on the desktop and select "Personalize," to open the "Personalization" window. In the left-hand pane, click on "Change Mouse Pointers" to open the "Mouse Properties" window shown in fig. 2. If you are unable to do this, use the following alternative method. Otherwise, go to Step 2.
Open the Ease of Access Center window by pressing the Windows key+ U, or by clicking the "Start" button, followed by "Control Panel," then "Ease of Access," then "Ease of Access Center." Under the "Explore all settings" header, click on "Make the mouse easier to use" (as shown in fig. 1), or press Tab until it is highlighted and then press Enter.
Step 2: Swap the primary and secondary mouse buttons
If it is not already selected, click on the "Buttons" tab, or press Tab until any of the tabs is highlighted and then use the arrow keys to select the "Buttons" tab.
Under the "Button configuration" header, tick the box next to "Switch primary and secondary buttons" by clicking on it, or press Alt+S to tick it.
Click the "OK" button or press Enter to finish.