Correlation functions, S-matrix elements, the LSZ formalism. Reading off Feynman rules from an action. Fermionic variables.
Dealing with divergences, "dimensions change when you change dimensions," β function, Wilsonian effective field theory and theory space, Kallen-Lehmann spectrum.
"Renormalization and Effective Lagrangians," Joseph Polchinski, Nucl.Phys.B 231 (1984) 269-295
"Effective Field Theory and the Fermi Surface," Joseph Polchinski (hep-th/9210046)
"Renormalization of a model quantum field theory," Per Kraus; David J. Griffiths, Am. J. Phys. 60, 1013–1023 (1992)
"Learning quantum field theory from elementary quantum mechanics, P. Gosdzinsky; R. Tarrach, Am. J. Phys. 59, 70–74 (1991)
"Anomalies in quantum mechanics: The 1/r^2 potential," Sidney A. Coon; Barry R. Holstein, Am. J. Phys. 70, 513–519 (2002)
Of historical significance:
"Memories of a Theoretical Physicist," Joseph Polchinski
Gauge symmetry versus gauge redundancy. Gauge fixing and the Fadeev-Popov procedure. β function for gauge theories. If time: soft theorems and infrared divergences.
"Why Gauge?" Carlo Rovelli (arxiv:1308.5599)
"What does the R stand for in Rξ gauge?" (physics.stackexchange question 434102)
When a theory is "mathematically wrong." The Fujikawa method. Anomaly coefficients. Chiral fermions.
"Anomalies for pedestrians," Barry R. Holstein, Am. J. Phys. 61, 142–147 (1993)
Goldstone's theorem, Goldston boson equivalence, electroweak symmetry breaking. How far yoiu can go by just writing out even index explicitly—a.k.a. "group theory without theory."