Hi Colin here,I have a ddb puppy who is 10wks old and he has started to show some signs of agression,It's nothing major at the moment but i want to stamp it out now before he gets older and it could become a big problem.It's seems to be mostly when we are playing he will sometimes start to growl and snap but not just in a playfull way and when i tell him off he faces me up and starts barking,growling and snaping and normally i just stand up and point my finger at him and tell him a firm NO and stare him down,but it usually takes a while for him to back down.I was wondering if anyone could give some advice as to the best way to deal with him when he's like this as i don't want it to get out of control.

I'm not sure why you are so convinced this is "not just in a playful way" - puppies can be very vocal, play-snap and play growl at each other and it's all a normal part of play.  Nothing which you've said so far is anything to discourage.  When you tell him off, he just thinks you are playing and joining in with his play.  If you don't like something he's doing, it's far better just to walk away and ignore him.  Here is a link about puppy play biting:

<a class='url' href='http://www.jersey.net/~mountaindog/berner1/bitestop.htm'>http://www.jersey.net/~mountaindog/berner1/bitestop.htm</a>

I guess you are concerned and understand why, however I agree this is normal.
I know it may be tempting to try and control him by being "dominant" but you don't need to do this.

The best thing you can do IMO is to quickly book him into a puppy class but be sure it is a good one as a poor one can be worse thatn none at all. With a ddb as with any breed, they need thorough socialisation to humans and dogs asap, before 16 weeks ideally. Try www.puppyschool.co.uk or www.apdt.co.uk and you will hopefully find one near you :)

It sounds to me just like classic confident little pup behaviour rather than a precursor to aggression problems and I'd certainly go for ignoring the behaviour or diverting him into something more constructive rather than trying to stare the pup down which he will think is part of the game. At this age he'll easily get over-excited and this often accompanies over-tiredness. At only 10 weeks he needs a huge amount of sleep and, like small children, pups aren't always very good at realising they need to go to bed!