Just washed out two flasks, thats a start at cleaning stuff right? Mwahahaha
Serious though ,
pour pot of coffee into flask,
take with you to where you'll sit or be,
turn the coffee machine OFF,
but on a key meter sometimes that matters.
The same If you boil a kettle.
Use water you need,
then pour rest into flask so you dont have to boil again later.
Thats why I have two flasks.
Theyre also handy if out,
I take the metal one when out so the plastic one with glass inner cant be broken. Prices are too fecking expensive in even the cheapest place for coffee. Unless its free, of course.