First, I used the hot glue gun to secure the canister to the base. I felt it looked a little unstable, so I glued a couple of polystyrene offcuts either side of it to resemble earth built up under it. There was a screw clearly visible at one end, so I popped the back of an old Imperial Guard searchlight over it. I sawed the nozzle off the other end. I used some bits of spare scenery from a company I cannot now recall to cover the subsequent hole. I cut two thin strips of plasticard and superglued them around the main body as it looked rather bare. I applied rivets to these strips and to the ridged area that was part of the original canister. If rivets wouldn't stick, I drilled a hole to suggest they'd popped out.
Then I applied PVA, got sand over everything, let that dry, and hit it with a diluted PVA to lock the sand in. Once that had dried I hit it with a basecoat of Halford's yellow car primer. Then I covered the contained itself with Army Painter's blue spraypaint. Then I mixed some Prussian Blue Boldmere acrylic paint with a little Games Workshop Chainmail and water, and applied that over the top of the Army Painter. After that, I applied a slightly diluted layer of GW Asurmen Blue wash. The goldwork first received a layer of GW Shining Gold, then a layer of Citadel Colour Burnish Gold. I wonder if they still make that. I then applied a GW Devlan Mud wash, before picking out rivets and some details and scratches with GW Mithril Silver. I used some brown house paint for the brown on the base, but that needs another couple of layers, as you can see!