Today I'm using an Imperial Guard (Astra Militarum) Stormtrooper (Tempestus Scion) to demonstrate the technique that I use to speed up the painting process on my non-Tyranid models. This relies on two key elements- changing the order of operations to put shading as the final step, and using a wash with the right mix of physical properties to provide good shading without overpowering the rest of the model. For maximum speed, as on my Death Korps and Renegade Militia, it's as simple as basecoat, one highlight per color, and then an all-over wash. You can find more examples of these models on my Instagram:
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