I also agree with the GL or Halti approach - you can redirect the head and have your puppers focus back on you and away from that exciting other dog approaching
I'd also start teaching a 'look at me' command - so when that other dogs approaches, you can give the command and your dog is more interested in looking at you.
With Loki - I taught him that a cluck of my tongue (I was too lazy to get a clicker..) meant for him to look at me and he got a really high value reward. We practiced it lots and now we can walk by other dogs with no problem - in fact, he looks at me before I even give the signal now
As long as you're very sure your dog is just excited and it's not a reactivity issue or fear... in that case, I would suggest you look up and practice BAT: http://functionalrewards.com/
Good luck to you