Each night I have to charge my camera battery and transfer my pictures onto my computer. But in the past I have forgotten to put the battery/SD card back into my camera and end up not being able to take any pictures all day long. So to make sure I don't forget them I like to leave all the (battery and SD card) slots on my camera open. That way when I take my camera in the morning I will see the open lids and remember to put the battery/SD card back into my camera. Here's a picture of what I mean...
Another thing I do (as a second check) is to take a random picture with my camera before leaving my hotel room. If your battery is missing then obviously your camera won't even turn on. And if your SD card is missing, most camera will show a message telling you that it is missing.
Hope you find today's tip helpful!
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