(Cracksman replied with a similar method whilst this post was being typed, but I'll leave it as it is.)
Dev:
It has been suggested in the past, to cut out the paper template and lay it over the blade stock, then spray paint over it. Remove the template when dry, then remove the painted metal with the grinder. This be helpful in not getting the metal too hot, otherwise the paint will blister. Regular quenching will keep the painted outline intact.
I prefer to scribe the rough outline onto the blade, then make increasingly lighter passes on the grindstone as I get closer to the outline. Leave a small amount of material outside the line before switching to the Dremel, as this will also remove material.
To manually remove grinding irregularities and make the curves smoother, you could draw-file with a round/half round file on the inside curve, and a mill file on the outer curve. Once the curves are concentric, you can switch to the Dremel for powered smoothing, or continue manually with progressively finer grades of wet 'n dry sandpaper.