Britain cannot hope to invade Germany and Germany cannot hope to invade Britain. So all that's left is that Britain would be able to take all German colonies while the German fleet will probably stay in port after one big battle which won't manage to shift the balance of sea power in Germany's favor.
Britain cannot strangle Germany in a blockade as long as all other neighbors are still trading with it. Germany meanwhile will probably fail to make its submarine counter-blockade work since Britain will be able to concentrate all its attention on that.
In other words, this is a rather pointless war that won't ever reach big dimensions. Since Britain can occupy all German colonies and destroy its merchant marine, I assume that it would eventually be seen as a British victory.