The Hill Country’s Liza Proch decided to create something that people could take home after visiting Fredericksburg: a coloring book with landmarks and the signatures of the city. Following the book’s success, she released another in May — this time all about Luckenbach Texas.

She’s gathering ideas for yet another coloring book, full of “good things inside,” as her slogan says, and is also in the process of designing a series of stickers for the Texas State Parks, alongside the Freder...