Flatpicks and thumbpicks can easily be re-shaped using an emory board, fine files, fine sandpaper, or a fish hook sharpener. Some picks develop a slight burr along the edge which doesn't sound too good. Some others just wear down and need reshaping, depending on your preference of shape. Many thumbpicks are simply too long when new and filing them back and rounding over the edges will make them more comfortable to use. Likewise for fingerpicks.
Keep an extra flatpick secure and handy woven in the strings at the headstock.
Post-it notes are great for song "cheat-sheets" or set lists or other reminders, fastened to the guitar side.
More later. Mooh.