I often dine alone at restaurants because I personally find it to be more convenient and tasty than preparing my own food. On occasion, though, I find that I have to temporarily leave the table in order to visit the restroom. Even though I might only be gone for a few minutes, if the timing hits just right, it can happen that my table has been cleared because the staff thought I was finished eating and was not planning to return. (One could also imagine having to take an emergency phone call, and going outside to do it so as not to annoy other diners.)
Generally, I am mostly finished eating by the time that the urge hits me, so it definitely looks like I have abandoned the remaining food on my plate—but I haven't! I plan to return and finish, just as soon as I take care of this emergency business.
The consequences of this happening include losing the uneaten food that remained on my plate (which seems like a waste to me, both financially and otherwise) and causing the restaurant staff to think that I've skipped the check (left without paying the bill). This results in awkwardness all the way around.
When you're dining with others, this is simple. They know your intention to return, so they can just tell someone who shows up and tries to clear the table. But when you're dining by yourself, the table looks abandoned, and there's no one to convey your intent.
What can I do to indicate to the restaurant staff (e.g., a busser responsible for cleaning tables) that I have only temporarily left, and that I plan to return and finish my food? How can I convey that I am still eating?
I've thought about leaving some personal effects on the table to indicate my plan to come back. Obviously this isn't foolproof—the restaurant staff could assume that I just forgot my personal effects—but a bigger problem is that someone else could steal them. For example, I could leave my phone, but there's a good chance that it won't be there when I return. I have tried leaving my credit card to convey both that I plan to return and that I haven't skipped out on the check, but that isn't ideal either, as someone could easily pick up my credit card and walk off with it while no one is watching.
Anyone have other suggestions on how to indicate this simply yet effectively?