I seriously need some help with this deck... Any tips?

I'd say make separate decks. Put all of your zombie cards together in one deck, and synchros in another. Zombie decks all *require* 3x Book of Life, 3x Pyramid Turtle, 3x Zombie Master. Synchros-wise, you should go for a specific star number, such as 8. 8 stars can get you Stardust, Red Dragon Archfiend, and a lot more. To do this, just get 4 star tuners and 4 star normal monsters.