Use Goblins near the Giant opponent when he has passed the bridge and is in range of your tower.
Drop the Spear Goblins/Archers behind the goblins that they eliminate the enemy attacking from behind her Giant.
If the enemy drop a Valkyrie or Mini P.E.K.K.A, throw the servants as she is on your side of the battlefield.
Use Knight to counter a group of enemies (Goblins, Skeletons, etc) with Bomber, Minions or Archers comming from the back.
While you stand one side with one of these strategies, let your giant going slowly to the enemy tower on the other side. Starting from your defense field, near yout tower.
After he passes the bridge to the opponent side.
Drop a Bomber behind him.
The enemy will be forced to drop troops randomly on your giant. Prepare a shower of arrows and point to them. Fill the opponent's arena with your cheaper cards to put the enemy to despair.
Put melee attack cards right next to the giant and distance troops far closer to the bridge.
And of course, Good Luck and Have Fun!