Clearing Codes on a 1997 Altima

Hi,
I need help clearing the codes on my 1997 Altima. I don't have a scan tool so I have been trying the method of pressing the gas peddle 5 times in five secs. then wait 7 secs. hold for 10 secs. but the light never flashes. As such I'm thinking this is not the method on my year car.

Can anyone help me figure this out?

Thanks