Karen Saunders is THE go-to gal for creating one-sheets and other marketing pieces. Download the original 40-page tutorial she provided for us here (https://www.karensaundersassoc.com/pdfs/One-Sheet-Handout.pdf) -- and also check out her latest version HERE ($49).
It is so important for you to have "stellar" one sheet that floats to the top of any pile. While targeted toward speakers, this show is ideal for anyone who puts together publicity pieces. Karen Saunders is just full of great advice that will help you tremendously. You are going to LOVE the content of this show and find that the majority of it (except the older looking images) still applies today. Enjoy!