To type special characters available on the keys of your keyboard, press Alt Gr + the key corresponding to the symbol. For certain characters, you simply need to turn off Caps Lock and press the key of the desired character.
If you've a numeric keypad, you can press the Alt key and enter the code of the special character to type. If you want to type the equal = sign, use the code Alt + 61. You must turn on the Num Lock key for this to work. You can find the Alt codes you can use on this page.