How do I strore numbers on my phone

I was given a telstra slimline 40 handset. The neon one which lights
up when it rings.
Unfortunately I am a dunce when trying to store numbers on it.. have
tried different combinations of memory and store to no avail.
apart from the usual keypad, on the left side is recall button. On the
right of the keypad are the three buttons..from top to bottom, memory,
store and redial.
Would appreciate any suggestions.
Thanks
Gypsy