Controlling my tarpaulin all over the place covering nothing (12)

'controlling' is the definition.
(that which controls or manipulates)

'my tarpaulin all over the place covering nothing' is the wordplay.
'all over the place' indicates an anagram.
'covering' means one lot of letters goes inside another.
'nothing' becomes 'O' (O resembles 0).
'my'+'tarpaulin'='mytarpaulin'
'mytarpaulin' with letters rearranged gives 'manipulatry'.
'manipulatry' enclosing 'o' is 'MANIPULATORY'.