By hand for the big flat bits that you can see and get at, then spray the crooks and nannies you cant get at (but can still see) then when that has dried spray cavity wax or similar in all the bits you cant see but can get the straw/pipe into as the pressure washer will have gotten every where and you dont want it rusting where you cant see it untill its too late.

Nice job on the cleaning btw, you sure got a minter there!