How did I not notice this before it’s really easy to draw fluorescent lights in firealpaca
First switch your drawing setting from freehand to line. Trust me this will help a lot. Next select the color you want the light to be and set aside two shades of it, one off-white and one more fully saturated. If you’re drawing a white light, then just use white for both. After that, take the off white shade and set your pen/pencil thickness to however thick you want the bulb to be. Click and drag to make the initial line as long as you wish. Stop and make a second layer. It doesn’t matter how many layers you already have. Make a separate layer for the glow of the light that only has the glow of the light. It doesn’t matter whether this layer is above or below the bulb, just that it is separate. You can merge them later if you don’t want your layer window cluttered, just leave them separate for now. Now on this new layer, switch your color to the more saturated one, and change your brush size. Depending on the setting, the glow may be bigger or more intense than others. A rule of thumb is the glow line should be twice the thickness of the bulb. Next, repeat the process that you did for the bulb, exactly tracing over the line of the bulb. But when you’re done- and this is why we added a separate layer earlier- change your brush type from pen/pencil to blur. You can keep your setting at line, or you can change it back to freehand- because of the layering, it won’t make much of a difference. Set your blur intensity, again, this varies depending on the environment you’re drawing, but my go-to intensity is about 75. Make a quick swipe with the blur tool down the center of the glow layer, and voila! Fluorescent light.
If anyone wants pictures/gifs to make this more convenient to follow I’ll be happy to comply