Solution: Set a reminder to constantly revisit your stage plot and ensure that it's still an accurate representation of where things go on stage during your performance. Added bonus: put a cell phone of the band leader on the list so the engineer can follow up prior to the show to ensure it's still accurate.
Problem: The booking agent/band sends the house sound engineer a stage plot that shows where microphones go, where DI (direct injection) boxes should be placed, how many pieces the drum set is, how many vocalists there are, etc. The house engineer sets up the stage based on this to ensure a quick load in and sound check, only to have the band show up with a totally different set up. This delays sound check and could possibly make the gig start late due to the re-org that's now required by the engineer.
Background: There are a lot of moving parts in a band and we all understand that things change often, sometime daily (on the road)! Some examples include new amps, additional drums, mono keyboards to stereo keyboards, adding vocalists, removing vocalists, moving from floor monitors to in-ear monitors, moving stage positions for better cue visibility, etc.
Mitigation: Put one person in charge of this and send a copy to your agent/band manager regularly to ensure they have the most up to date stage plot. If kept in soft copy, naming the file the same will ensure that the previous versions are overwritten when re-saving, so as to never have multiple versions floating around.
Here is a site we found that will get you going on the basics for free. It doesn't have monitors but you could add those in with something else. Either way, this is just an example of what you need.
Here is an example of a simple yet thorough stage plot: Full Effect Stage Plot