Question 1: How do I add names or fix mistakes on a sign?
Adding names:
I use an extra-fine black paint pen (found in most art supply stores) and a stick and ball craft font. In adding to names already on the sign, you should practice on a side piece of paper to match the size and style.
Fixing mistakes:
You will need paint thinner, a Magic Eraser (sold at most stores) and a cotton makeup remover pad or several Q-tips. It is easier to remove the whole name rather than to try to just remove one letter. Dip the cotton pad (or a Q-tip) in the paint thinner and begin to rub off the name. This may take several tries with several new Q-tips. When most of the name is removed, the remaining can be cleaned up with a wet Magic Eraser.
Let dry and reapply as described above.