The most common and most likely answer to this crossword clue is the 11 letter word COUNSELLING
I've seen this crossword clue in The Daily Telegraph
C
O
U
N
S
E
L
L
I
N
G
Buddy explains!
The straight part
We know that "Advising" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case advising = counselling.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does COUNSELLING mean?
COUNSELLING verb- To give advice, especially professional advice, to (somebody).
- To recommend (a course of action).
- Assistance (especially from a professional) in the resolution of personal difficulties.