clap on

verb4

1. •
   To temporarily add something to an existing part, especially to add an additional sail to take advantage of a fair wind.

   • We spring out of our berths, clap on a monkey-jacket and south-wester, and tumble up the ladder. — 1840
2. •
   (UK, informal) To talk at tedious length; to whinge.

   • […] clapping on about having to live on a small income because of her son's lack of ambition. — 2020
3. •
   To encourage by (or as if by) applauding.
4. •
   (slang, old-fashioned) To decide to make a concerted effort to do something; to operate with dedication and vigor.