Thought I'd share these process pics of Nancy writing on the chalkboards for a menu project. She used a chalk-pen (as opposed to actual chalk) which you can purchase at any art store. The writing needed to be semi-permanent so it wouldn't get erased during shipping--it comes off with windex or soap and water.
She drafted the wording on paper first to get the proportions right and made pencil lines on the chalkboard to keep the lettering straight. Lots of prep-work to get it perfect!