Laid out advertisement about royal collection (8)
I believe the answer is:
arranged
'laid out' is the definition.
'arranged' can be an answer for 'laid' (arranging is a kind of laying). I'm unsure of the 'out' bit.
'advertisement about royal collection' is the wordplay.
'advertisement' becomes 'ad' ('ad' can be a synonym of 'advertisement').
'about' is an insertion indicator.
'royal' becomes 'r' (abbreviation).
'collection' becomes 'range' (I can't justify this - if you can you should believe this answer much more).
'r'+'range'='rrange'
'ad' going around 'rrange' is 'ARRANGED'.
Can you help me to learn more?
(Other definitions for arranged that I've seen before include "Settled plans for something" , "Placed attractively as with flowers" , "Put in order or adapted a piece of music" , "Put in proper order" , "Scored" .)