Eskies are designed to retain temperature. Obviously, this is why they're so great at keeping our drinks and food cold. And pre-chilling your esky can help keep it cool longer.
Photo by epic beer.
This tip comes courtesy of Epicurious. They explain:
...if you store your cooler in the hot attic of your house or the hot garage, make sure you bring it in the house and open it up to air out a day before packing it. Ideally, you'll want to get it cold. DJ Bell, the director of product marketing from Yeti Coolers, recommends dumping a "sacrificial" bag of ice in your empty cooler to chill it for at least a few hours before packing it. (Discard that ice before you start packing — it's done its job.)
You can check out the full post at the link below.
How to Pack Your Cooler for Camping the Right Way [Epicurious]