'Big wig' referred to the actual size of the wig, not it's fluffed up size. Take a look at the old portraits.

'Beeswax' is a slang construction from the early part of the century, a nonsense term. (ie. in the sense given)

Chairman of the Board? Picture every one sitting on the floor except for one person on a chair. It won't work. Again, look at old paintings. You won't find that set up anywhere.

'Mind your p's and q's.' supposedly arose in medieval scriptoria.