Officials are considering traffic signs, radio announcements and brochures as ways to educate drivers that holding a cellphone up to the ear to talk while driving or sitting in traffic will be illegal a year from now in New Hampshire. Gov. Maggie Hassan is expected to sign a bill that makes hand-held cellphone use while driving punishable by a $100 fine for the first offense. The price rises to $250 for a second offense and $500 for subsequent offenses within a 24-month period. The bill allows adults to talk on cellphones while driving if they use hands-free phones, devices built into the vehicle or two-way radios.