This recipe is designed to get close to the box art and is based completely off of GW tutorials and color schemes.  An extensive range of Citadel paints are used in this process.
  Basecoating
- Base coat main section of robes and hat with   Ushabti Bone  
- Base coat trim on sleeves, center of apron, and cords on right sleeve with   Mephiston Red  
- Base coat book binding, bookmarks straps, stole, and tube on side of servo skull in   Doombull Brown  
- Base coat servo skull's hoses and wires with   Abaddon Black  
- Base coat face and left hand with   Bugman's Glow  
- Base coat belt and boots with   Rhinox Hide  
- Base coat pouches with   Dryad Bark  
- Base coat servo skull with   Zandri Dust  
- Base coat pages of book, purity seal parchment, and rosary beads with   Rakarth Flesh  
- Base coat Inquisitor seals and large button under vents with   Celestra Grey  
- Base coat perimeter of sun icon within Inquisition seal with   White Scar  
- Base coat center of sun icon within Inquisition seal with   Jokaero Orange  
- Base coat purity seals with   Screamer Pink  
- Base coat gold plate and trim with   Retributor Armour  
- Base coat metal parts (hand, mace, ornate skulls, stubber, censer chain, servo skull augments, sidearm, buttons/clasps on pouches, port under vent, vox grill) with   Leadbelcher  
- Base coat bronze parts (trim on mace, stubber barrel cover, and censer) with   Balthasar Gold  
Shading
- Shade red parts of robes, parchment, rosary beads, and deepest recesses of lighter parts of robes with   Agrax Earthshade  
- Shade white perimeter of sun icon with   Casandora Yellow  
- Shade orange center of sun icon and skin with   Reikland Fleshshade  
- Shade lighter parts of robes and perimeter of sun icon with   Seraphim Sepia  
- Shade Inquisition seals (specifically the "I"), mace pommel, chest decoration, and purity seals with   Drakenhof Nightshade  
- Shade gold plating and trim with   Reikland Fleshshade Gloss  
- Shade bronze parts, red leather accessories, pouches, belt, boots, silver parts, servo skull tube, and servo skull with   Nuln Oil  
Layering
- Highlight lighter parts of robes, parchment, and rosary beads with   Pallid Wych Flesh  
- Highlight red parts of robes with   Evil Sunz Scarlet  
- Highlight skin with   Cadian Fleshtone  
- Highlight leather pouches, belt and boots with   Gorthor Brown  
- Highlight hoses and wires with   Eshin Grey 
- Highlight Inquisition seals, mace pommel and chest decoration with   Fenrisian Grey  
- Highlight servo skull with   Karak Stone  
- Highlight purity seals with   Pink Horror  
- Highlight red leather accessories with   Wazdakka Red  
- Highlight orange center of sun icon with   Troll Slayer Orange  
- Block out hazard stripes on servo skull wiring with   Averland Sunset  
- Highlight gold plating and trim with   Auric Armour Gold  
- Highlight bronze accents with   Fulgurite Copper  
Shading (Part II)
- Shade black and yellow wire with   Nuln Oil Gloss  or   Nuln Oil  
Edge Highlighting
- Fine edge highlight red parts of robe with   Wild Rider Red  
- Fine edge highlight leather pouches, belt, and boots with   Baneblade Brown  
- Fine edge highlight skin with   Kislev Flesh 
- Fine edge highlight servo skull with   Ushabti Bone  
- Fine edge highlight yellow perimeter of sun icon with   Screaming Skull  
- Fine edge highlight orange center of sun icon with   Fire Dragon Bright  
- Fine edge highlight red leather accessories and servo skull tube with   Squig Orange  
- Fine edge highlight Inquisition seals, mace pommel, and chest decoration with   Blue Horror  
- Fine edge highlight parchment and rosary beads with   White Scar  
- Fine edge highlight hazard wiring with   Dawnstone  (black stripes) and   Yriel Yellow  (yellow stripes)
- Fine edge highlight hoses with   Dawnstone  
- Fine edge highlight gunmetal bits, gold plating, and bronze plating with   Stormhost Silver