Drink up in right royal style! (5)
I believe the answer is:
regal
'right royal style' is the definition.
Both the answer and definition are adjectives. Perhaps there's a link between them I don't understand?
'drink up' is the wordplay.
'drink' becomes 'lager' (lager is a kind of drink).
'up' says the letters should be written backwards (in down clue: letters go upwards).
'lager' in reverse letter order is 'REGAL'.
'in' is the link.
Can you help me to learn more?
(Other definitions for regal that I've seen before include "Imperial, majestic" , "Kingly glare?" , "King-like" , "Portable organ" , "fit for the Queen" .)