We've got a row of conifers at the end of our garden, closely abutted
and fairly thick, but they're really tall (15ft+) and leggy.

Can anyone tell me what I need to do in order to turn my tall, messy,
leggy conifers into a lower, more compact hedge?

Sorry, don't know what species/variety they are. Definitely NOT
leylandii though.

Thanks so much

David