This tutorial will cover how to paint the flies, for Blightlords (skin, armor, weapons, etc) and bases, follow the Blightkings tutorial:
Airbrushing
This will cover basecoating and aibrushing of few parts at once, as it'll be hard to paint every part from start to finish without spraying over on other parts.
Airbrush the bodies of the flies from the bottom with heavily diluted Rhinox Hide . Do it multiple times to get the coverage, while keeping the mix thin for nice blending.
Using similar dilution of Rhinox Hide , airbrush the wings close to the wing "bone/spine" parts, leaving Greenish White visible on the thinnest parts.
Airbrush the wings with Malignant Green leaving thinnest parts of the wings as light as you can and focusing on the middle of the wing.
Body
Boost the shadows even further with Rhinox Hide , apply thin layer consistency to the deepest recesses and feather it towards the midtones.
Use heavy glaze consistency of Filthy Brown to tint the body of the fly yellow. It could be airbrushed, but tinting by brush will give you smoother, less "chalky" results.
(optional) Add your preffered pattern on the back of the body with Rhinox Hide .
Mini painter first, Age of Sigmar player second. My two main reasons to go bankrupt are Orcs and Nurgle, but Gitz and Skaven might join the list soon...