I'm a bit concerned that maybe the manufacturer tried, but never got a good aerator working on that shape spout. But if If you want to try, first, take apart a typical aerator and see how it works. There's usually several stainless steel screens, one stacked on top of the othereachother. Plus, there's a plastic flow-evener. You can bybuy stainless steel screen on eBay in big chunks, so that's not a problem. You'd cut them all in the same shape, but some cut on a diagonal. You just need to figure out the grid size for the screen, which you can look-up on wikipedia. You might get a rectangular bit of plastic and drill holes in it to make the flow-evener (creativity required here). And and you would need a picture frame shaped 'something'object that would be the last bit to go in. That would hold the SSstainless steel screens you cut, and your plastic flow-evener assembly. Probably your biggest problem will be having a way to introduce the assembly into the spout so you can insert it and remove it, but not have it pop off when the water gets turned on. If you don't mind drilling holes in your spout, you could get some small stainless steel screws to hold the assembly in place.