Have you screwed up a lot of different things? Do you want to hide the worst of your screw-ups? There's an easy way — just tell people only your smallest mistakes.
When people have to remember a long list of things, you can erase some of the items on their mental list by prompting them with other list items. If they're anything like the participants in a certain memory study, they'll fall for it.
The study was meant to peer into that murky land called memory. Do we remember things independently of each other, or do memories depend on each other? To find out, the researchers gave the participants a list of items to remember, and then asked them to recall the items some time later. One group of participants was asked to remember as many of the list items as they could without any help. The other group was prompted with a few items from the list. It seems like that group that received some of the answers would do better overall, but it didn't turn out that way. The unprompted group did better than the group that was fed some of the answers. Something about being reminded of some of a list of items makes it hard to retrieve the rest.
So if you need someone to forget one item on a list, be as helpful as you can be with every other item. Keep prompting them until they can't remember anything that you don't tell them.