Misguidedly being open! (5)
I believe the answer is:
begin
'open' is the definition.
(I've seen this in another clue)
'misguidedly being' is the wordplay.
'misguidedly' indicates anagramming the letters.
'being' anagrammed gives 'BEGIN'.
(Other definitions for begin that I've seen before include "Institute" , "Commence" , "former Israeli Nobel peace prize winner" , "Initiate" , "Israeli statesman" .)