Bill navy after installing bit of outside deck (5)
I believe the answer is:
adorn
'outside deck' is the definition.
'bill navy after installing bit of' is the wordplay.
'bill' becomes 'ad' (advertisement stuck on wall**).
'navy' becomes 'rn' (abbreviation for Royal Navy).
'after' is a charade indicator (letters next to each other).
'installing' indicates putting letters inside (I've seen this in other clues).
'bit' suggests taking the first letters (I've seen 'bit of' mean this).
The first letter of 'of' is 'o'.
'ad'+'rn'='adrn'
'adrn' placed around 'o' is 'ADORN'.
Can you help me to learn more?
(Other definitions for adorn that I've seen before include "dress" , "Festoon" , "Beautify - decorate - enhance" , "Improve appearance" , "Embellish, decorate" .)