http://www.gamefaqs.com/xbox360/943397-deadly-premonition/fa...This is a walkthrough to Deadly Premonition, with all Side Quests and Trading Cards detailed.
Episode 1 consists of Chapter 1 to 7. There's only a couple of Chapters where you have to fight enemies.
Get the Infinite Wrench in Chapter 2, and it will make light work of any threats (One hit kill on shadows). Use Chapter 2 to get a lot of the trading cards, making your life easier.
You may also get the Infinite Submachine Gun in Chapter 6. Buy the Map from Keith at the Milk Barn for $1000, starting the quest "Map To Psychic Spot A. Follow the Gold Arrow to the tunnel and you will teleport in to an area where you have to go room by room, killing the enemies as you go. The second to last room has about 8 enemies, all wielding Shotguns. With the Infinite Wrench, this is a piece of cake.
The final room will have your Infinite Submachine Gun.