Usually when a second colour is needed the first one is masked. No problem with dark colors as they cover very well. Not so with colors with less covering means, especially dayglo orange. Usually a second or even a third layer is necessary.  But then the paint edge can be very prominent, a ridge than can be seen and felt. Another problem may be the masking tape itself. Too sticky and it removes the underlying paint.

When a soft edge is needed tape can't be used. But if the model is to show a perfect straight edge spraying may result in a slightly wavy line

Solution: Mask doesn't adhere to model

The template (or simply a straight edged cardboard) doesn't rest on the model itself, and secondly, as there isn't a tight fit needed, something only moderately sticky could - and should - be used (agent to your choice, perhaps some doublesided glued tape, stickiness reduced by handling with your fingers). Humbrol Maskol is ideal.

Materiel of the masking to your choice, preferably thin cardboard, in some cases  paper will do.

General rule:  How soft/hard the edge gets depends on the distance of the template. Principle as follows:

	Conventional spraying: Paint particles are stopped and collected at the masking tape resulting in a ridge. Please note: Distances und measurements only for clarification and not to scale!
	Spaying over a template, distance small: Slight angle of airbrush prevents paint creeping below the template. Vertical use is possible, but only a slight deviation in the wrong way may cause unwanted results.
	Spraying over template, distance bigger: The so called "Coanda Effect"  causes a small portion of paint particles to creep around the edge of the template creating a soft paint edge.
	Never (pas jamais) in the direction of the template!
	Mask for spraying a straight line on the fuselage of an aircraft.
	Idea for different  use.