lilly is right, dont drag your teeth no it.if he is small slide your mouth all the way down his shaft and hold it there for a few sec; then make your mouth as wet as posible and take long full strokes with your mouthletting the head come 3/4 of the way out of your mouth then take it all back in.start geting faster and faster and make plenty of slurping noises,let some spit come out of your mouth and make it kinda slopy.," if you dont mind cum in your mouth"when he starts to cum KEEP SUCKING, dont just stop. for a large penis i like to keep the head in my mouth and stroke him off untill he cums. if you dont like cum in your mouth thats ok to , when he starts to cum just slide it out of your mouth and stroke him off but make sure to let him cum on your face,most men rather cum on your face anyway, i guess this makes them feel powerful. the main thing is be confadent, act like you know exzakly what you are doing. folow these guidelines and even if you have never done it before he will think you are a pro, he will not beleaive how hard you made him< cum,when you went down on him.....good luck