Quantum Field Theory is a notoriously difficult subject to learn, but I found the following resources to be extremely helpful. If you have any other suggestions, send me an email.
Tony Zee's book QFT in a Nutshell provides a great intuition into what QFT is all about. If you actually want to do calculations, then Peskin and Schroeder's book is a nice compliment. These two books were the heart of my studies into QFT.
David Tong's Notes:
Great set of lecture notes. He provides a different perspective here.
Sidney Coleman's Lectures: