When you dig a hole you make it deeper and deeper. The idiom to dig a hole for yourself means to put yourself deeper and deeper into a bad situation. When you dig a hole for yourself you say or do something that puts you in an embarrassing or difficult situation. Similar in meaning to put your foot in your mouth.

1. The game is up now so just tell the truth. By continuing to lie all you're doing is digging an even bigger hole for yourself.
2. Don't use your credit card again until it has been paid off or else you're just going to dig yourself into a hole.

1. I dug a bit of a hole for myself by promising the client that I would have the order completed in a week. Realistically, I'd need at least 10 days.
2. Alice managed to dig a hole for herself with her speech by making a joke about the boss that did not go down well at all.