You'll see that I did a test in spare wood first - and subsequently altered my design. I always and strongly suggest you also practise away from your sign first.
Notice the way the design works with the tools. Once you understand how I construct the volutes within the fiddlehead you can adapt to the tools you have. Never mind my drawing; your tools have it.
Also notice how the repetitive nature of the carving is reminiscent of mouldings. Do have a look at some of these in the Ornamental section of the website. Working like this gives a wonderful rhythm to the design.