The biggest factor in photography is lighting. Unless you are 100% in control of the lighting (as in a studio), there is never a predetermined group of settings a particular situation that will work 100% of the time...MAYBE 50%, but even that's pushing it.
A MAJOR factor in photographing neon signs per your plan, is that you'll have to do your photography after nightfall, or perhaps at dusk. Otherwise, the neon won't be very bright and be washed out by sunlight. Nighttime photography adds a whole slew of other photography issues, including stopping camera shake motion and mixed and varied light source types...aka, white balance will be difficult. If you have a grey card with you, take a close-in shot of that to use to set the starting point for WB during post processing.
So how would I shoot the signs? My first step would be to push up the ISO speed a couple of notches...2400 or so. To stop camera shake, shutter speed should be about 1/60th or faster. If you want to freeze people walking, 1/250th or 1/500th. Then think about depth of field. At wide open (f1.8) on your lens, at 10 feet, your DOF is about 8". At 50 feet, 21 feet DOF.
Online Depth of Field Calculator Stopping down a bit will give more DOF to capture more of the building, or at an angle to the building, and keeping it in focus.
Since each photo you take is effectively free. Take a test shot or two and then look at the results. Too dark? Too bright? If the lights are on inside the storefront, you may have to move around to minimize seeing inside the store vs seeing the neon in the window. If you're able to zoom in the LCD image, look closely at the neon. Sharp and in focus? It's long been said that camera settings are at best, a compromise. In short, what are you willing to 'give a little' on to get the shot you want? Too much ISO, noise gets problematic. Too slow a shutter speed, camera shake or blurred moving objects. Too wide open, too 'thin' a depth of field.
And as you move around taking multiple pictures of the same storefront, double check the LCD every now and then as lighting and everything else will have changed...and adjust as necessary.