How did Romans knot sandals?

I wonder if there is any evidence how Romans tied their sandals - the final knot rather than the lacing. Was it a common bow tie?

Maybe you have seen recent videos on how most folks naively tie shoelaces into a slipknot rather than proper one. The slipknot tends to make the bows sit crooked as below, but you can tell best by grabbing the non-loose lace side of the knot and seeing if it slips. Instead of tying the bows an additional time, (ugly and hard to untie) you can just retie it with the initial overhand knot reversed.

For more security, I hereby mandate the easy variation "Parisian knot"; maybe the Romans called it the Gaul knot. After making the first bow, wrap it along with your finger twice instead of once before pulling the second bow thru. You may have to adjust it slightly so the double clenching of the bows sits tidy in the middle (check for slip too). Of a dozen bow knots I think it is the cleanest extra grip one, especially worth the effort when you leave it always tied: