For the kiddies
when sparring adults don't go power shot for power thats just gonna get you hurt. Get in and get out thats the only way to beat a guy who has more power than you. Also when sparring adults know that the power they use is the same they recieve from poeple their age so its not personal they expect you to throw that type of power when sparring at you.
For the geezers(me included
Most young adults that aren't black belts have a small fear of us. Its nothing that they won't get over but its still there so for the first few seconds they'll be hesitent. Or all you have to do is land a well placed round house kick to make them respect your power. Once their hurt they'll even be more hesitent to attack.