Enable the Numeric Keypad on a compact wireless keyboard,how to make it?

Compact wireless keyboard generally forgo including a separate numeric keypad, in the interest of saving space, and instead double up the functions of some of the keys on the keyboard. A small number or icon underneath the keys primary function label generally indicates the secondary function of keys on such keyboards. Most compact keyboards assign the keys found in numeric keypads to the right-most block of keys. Accessing the numeric keypad function isn't always as easy it is would seem, though.then how do you always make it?