If you have new sails, you’ll be wanting to get the numbers and insignia on them – and if you race internationally then you’ll want your country code as well.
Where is this all defined? Read through your Class rules first, and then for at least the international classes, you’ll need to check what it says in the Radio Sailing Appendix (E) of World Sailing’s rules…. subsection “G”.
Most of it is there I think, letter size(min max), gaps, which side is highest (starboard), distance between rows and all of that.
You can use stick on numbers if they comply, but I feel most people use an indelible pen. BG Design does great stencils in the correct size (if you tape them together, you have the correct gaps) and can supply an appropriate pen. In the end, I went to the local stationers and bought two indelible pens – a superfine and a chisel ended felt pen (much more versatile than a round point).
I taped the BG stencils in place, traced around with the superfine. The error to avoid is ink leaking under the stencil, so keep the pen moving quite quickly. Then I removed the stencils and used the chisel ended pen to “colour in” the outlines. Worked well. There are some good hints and tips on the Sailsetc website. Worth a read.
Take a look at Rules Appendix E here:-