Massive weight difference.

[Oahngoji]

Use up your opponent's energy. By doing that, circle or make quick movements to confuse your opponent. When you get aa chance of seeing an exposed opening of your opponent, strike that spot.

[Andrew_Patton]

Don't fight in a line, move out of the way, stay out of their way (sidestep). if you don't need to don't waste time blocking. And Never, never stop moving, you don't weigh as much you should be able to run circles around them.

[radicalspiegal]

Speed and snap kicks.

And a good follow up.

There is a fellow student in my class, he is 6 foot 4 and 250 + and im no daisey myself, i stand at 6 foot 1 and 175 lbs. But he actually throws me. until recently i have been really practicing my fakes and stutter steps and ect, then using my longest limb....my legs....i have been kicking with anklets on and been stretching dailey....but this is just me, i just kept watching video of my sparring and I try to fix everything I see, that helps too.