[ALUG] Boot menu

Now googling to find out what to press to get to the boot menu usually brings up suggestions to hit the shift key. I keep trying this but am not having any joy. Esc doesn't get me far either. Do I simply need to keep trying or are there any other options? Does it make a difference that I'm using a laptop? I get 10/11 seconds till the Mint logo appears if that's any help. It's all rather frustrating. Thanks in advance. Bev