What makes a password secure?
There are a few key points to keep in mind when creating a password. The best passwords are a random selection of letters (capital and lower case), numbers, and symbols (such as $,%,^, etc). Your password should be a minimum of 6 characters in length, but its security will greatly increase if you make it longer. Of course, under no circumstances should you share your password. If you do tell someone your password you should change it as soon as possible.
Step 1: Click on the Apple icon in the top left hand corner of the screen. Then, select “System Preferences.”
Step 3: Click the Lock Icon in the bottom left hand corner of the window and enter your password. You can now select an account in the left panel.
Step 4: Select the account whose password you wish to change. Click “Change Password” in the right panel.