Good response. My other bike has spokes. This is what I've found to be best.
Cut an old t-shirt into strips about 1" (25 mm) wide. Dampen a strip and wrap it around a spoke two or three times. Pull the ends back and forth while moving the strip up and down the length of the spoke until it is clean. Some simple green sprayed on the damp strip might help. Repeat for every spoke. Rinse very well.
Very time consuming. I I'm going to do this I often wait until I change tires and have the wheel on a wheel stand. Once, in the last 10 years, I even polished the spokes the same way.
As for the rest of your bike: I find the best way is a bucket and sponge. Lots of warm water in the bucket and a car shampoo of your choice. It doesn't really take a very long time and the results are quite good. As per your owners manual, don't use pressure washers.
I use a washing brush, I think I got it from Griots Garage. It has long soft bristles, it takes me 1/2 the time as when using rags, and no scratches. I start with the shield and bodywork then the frame, engine, and lastly the wheels. It works fine on the cast wheels but I have a smaller brush to use on the spokes. After I'm done I rinse any dirt and grit out and it's ready for the next wash.