miles plus money

Hello
It says you can use your miles for "miles plus money" on someone else's flight
https://www.virginatlantic.com/gb/en/fl ... money.html
"Miles Plus Money can be used when the booker is not travelling i.e. you are booking on behalf of someone else and wish to use your own miles to discount the traveller’s booking."
How do you do this ?
Thanks!
It says you can use your miles for "miles plus money" on someone else's flight
https://www.virginatlantic.com/gb/en/fl ... money.html
"Miles Plus Money can be used when the booker is not travelling i.e. you are booking on behalf of someone else and wish to use your own miles to discount the traveller’s booking."
How do you do this ?
Thanks!