Tips and tricks

I just brought the Diddy Kong Racing on a computer store...haven't played it since 2001, and I forgot to start boost on this game :( Can anyone help me?

you might already got it since its been some time, but you have to press A as "Get ready" is fading, just when its almost gone. btw you're an swesome mario kart player but i will be mad at you if you beat my dkr times ;)