Though not as well-known as "The Last Post", "The First Post" Bugle call is played in military forces to mark the start of the day, while The Last Post (or Taps) marks the end of the day. Both the First Post and Last Post are long calls made up of smaller phrases and some of those phrases are common to the two calls. Other calls used to mark the start of the day include Rouse, Charlie Reveille, Reveille (UK) and Reveille (US). See the links at the left to download the sheet music or audio files. More bugle calls are listed in our article about the history and cultural impact of Bugle Calls
The image below is the first page of the sheet music, and here you can download the full sheet music for The First Post (bugle call) in PDF format.