The thing about incise carving is that it goes faster, but is actually harder to do than raised carving. Why? Because incise carving is a ditch in the wood. If it's in the wrong spot, or too wide, you can't fill it in. That happens with all carving, where you get an "elbow" that develops in a curve that needs smoothing out. With raised carving you can alter the shape somewhat in other spots to make it smooth.
Key to both of course is your drawing. Spend PLENTY of time on that. Draw, erase, repeat until satisfied. Then start with very fine push tools. At first you're barely going to cut in a line, like 1/32" or even finer. Look at it. Odds are that there will be an "elbow" (or several) that aren't too smooth in the curves. Now you actually CAN correct it. When widening the incise you can cut more off the inside, and then the outsides where needed. If it's REALLY off (and it shouldn't be too bad because of all the time you took in drawing) you can cut another, because the scratch is so shallow it will just sand away when you are preparing the stock for finishing. Keep widening and deepening the cuts until you are at your final width and depth.
It's best to do one carving area (the butt carving for instance) all at once rather than individual tendrils and volutes until you're happy with that one individual. That way you can step back and look at the whole. carving in totality (I call it the 3' rule) to gauge the overall impression. There will be a central focus area where your eye naturally centers, and then things will radiate outward with your eye's attention. Just go slow. I take a LOT of time in carving. I might spend as much as 40-50 hours on each carving attention area [butt, wrist, tang, enter pipe (sides and bottom)] between drawing, erasing, and carving.