Push these Fan Ducts in the gap between Extruder Fan and mounting. The Fans will cool your print as well the extruder.
These are improved versions of my earlier Clip-ons and have a bigger mouth and more airflow.
You have to reverse the fans by turning them 180 degrees (so they blow in the other direction). I have added some shorter washers to replace the original ones, otherwise the mounting bolts of the fans/extruder aren't long enough.
Print them with 2 shells, 100% infill and full support. Of course the support has to be removed.