Practice what (one) preaches spoken language verb phrase
To behave the way one tells you to do.
She always practices what her mother preaches. If her mom tells her to go home at ten, she will never go home at 11.
Most parents always want their children to practice what they preach.
If you tell me not to be late, then practice what you preach.
A funny fact is that many people tell others to do things, but they themselves don't practice what they preach.
following closely behind someone
stop following, stop disturbing
To work or perform flawlessly or smoothly.
It's mostly used in the present tense.
Use ink or some type of digital scanner to record one's fingerprints
The police wants to roll all people's finger prints in the office.