The most common and most likely answer to this crossword clue is the 5 plus 3 plus 6 letter word GRASP THE NETTLE
I've seen this crossword clue in The Times
G
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P
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More clues leading to the result GRASP THE NETTLE
- Understanding 60 per cent of these irritate, act decisively
- To understand online system, regularly tell ’em to just go for it
- Good soldiers, with power at that time in land, set about difficult task
- Take on challenge sent Telegraph mad — about time!
- Understanding the web, let out to deal with problem
- Take a difficult decision and risk being stung
- Embark on challenge and risk getting stung
- Understand the web — time the French deal with problem
Buddy explains!

The straight part
We know that "just go for it" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case just go for it = grasp the nettle.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.