Here are two construction tips which you may find helpful. The first tip involves a way of taping off a hull to paint it's deck. I wanted to protect the hull's paint where it and the deck meets to prevent over spray and not have the tape rip off paint when the tape is removed. The best tape I have found to not rip off paint is the waterproof First Aid Tape made by Johnson and Johnson. It lays down well and if needed can be pulled up for correction.
Once the First Aid Tape has been placed to mask off the hull, the next step is to tape newspaper to the First Aid Tape with brown paper tape. Note: Don't put any tape on paint until it has dried for at least a week! Now you may paint without any problems.
The next tip is about sail numbers. Painting them on are too much labor and stick-ons can be too stiff. Not any more! True Value Hardware sells for 25 cents each, Dyer All-Purpose Letters and Numbers. These numbers are flat black, waterproof and are flexible vinyl. Their size are 3 1/4" tall and 1 1/2" wide.
An update to the sail numbers, I just installed the vinyl numbers above with great success! They went on easly (just be carefull, they stick fast!). Once you have decided where to put them, use a straight edge for a guide. Then to stick them on right, each number has a paper backing which splits in to in the middle. Hold down the botton half of the number and bend the top half back and peal off the top half paper backing. Let it fall down on the sail and then press it down then bend and peal off the botton paper backing and let it fall and stick.
It would be best to test an junk number on a scrap piece of sail cloth to get the hang of it. Once on, these vinyl number forms well to the shape of the sail. Can't beat that!