Where to look while playing
Set up a clear view of the people who can change the song.
You need enough chart information to know what comes next and enough eye contact to notice when the plan changes. Put the page where a quick glance gives you both, without blocking a cymbal or forcing you to turn away from the band.
Agree on the cues
Ask who calls repeats and endings, what the cues mean, and how early they will be given. A raised hand is ambiguous until the band agrees whether it means repeat, stop or watch for the next instruction.
At rehearsal, practice one unexpected repeat and one ending while playing a familiar groove. Look up before the section boundary and follow the agreed cue. If you miss it, find out whether the cue was late, your view was blocked, or you were reading information you could simplify.
Make the page easier to glance at
Write section names and changed bar counts where you can find them quickly. Keep the cue you need near the relevant passage; a note buried on another page is difficult to use mid-song.
Run the passage again from the section before the cue. The test is whether you can keep playing, see the signal and make the change together. Move the stand or improve the chart if the same problem returns.