Try to shoot at twilight, not at night. A deep blue sky is much more interesting than black.
Assuming you are shooting the 'whole' scene, F8 (i.e., don't care)
If you are closer in, then you'll need to consider DoF. Otherwise,
shoot in shutter priority and vary the shutter speeds to stop or blur the motion.
Try tungsten white balance, to really pop the twilight sky blue. Don't shoot it all in tungsten, but you might like how it looks.
Not so convenient in public, but yes. At the very least a monopod.
The rest is good advice too.
Yup, unfortunately never really convenient, yet oh so critical to good stuff. The favourite 'odd' notion I was told about tripods is that they don't have to go on the ground. That opens up a whole lot of new uses - have the legs collapsed to the shortest point, lean it against a wall and press into it.
Or take a table tripod and place it on a wall, or lean against a lamppost etc.
If you're less likely to get a steady shot try panning elements of the wheel or spinning the entire camera in track with the motion. You could also try zooming while shutter is open which can work nicely if you have an IS lens giving straighter 'vanishing point' perspectives.
If you can get close try resting the camera on the ground, looking upwards and shooting with cable release or timer. Makes for dramatic viewpoint, especially with figures silhouetted. Just point and shoot and see what you get.
I concur with Gordon's advice, and also with the advice to shoot RAW if you're comfortable with that.
There are numerous ways to stabilize a camera, and the key to getting really good shots is camera stability. Any shake will have a noticable negative impact on your results.
As everybody has said...dusk, tripod, long exposure, low iso, also I think wide angle lens works better.
Real nice. Dusk works particularly well with those sorts of colours. The warm reds really come forward and the blue retreats to the background. Gives a lot more depth due to the colour relationships, when compared to a shot with a black sky that feels much flatter.
A tripod or monopod is not absolutely necessary--if you have image stabilization. :-)
Here's a handheld shot that I took with an exposure of one second...
It does work, particularly at small sizes, but the stationary lights in that shot are blurred as well. Works well for web display but would suffer pretty quickly printed beside the same shot on a tripod. Certainly better than without IS.
