ngoti8tor

First rule is to make sure you have the weight distributed correctly.

acdii

Or how many don't have a clue they are a foot over the white line on the shoulder or those who drive with two feet leaving the brake lights on all the time. Could go on and on.

Wanna Ride

All above is accurate, but at any rate and for whatever reason, if you don’t have trailer brakes, don’t jump on the brake pedal! It’s a knee-jerk reaction, but don’t do it. In fact, don’t jump off of the gas, either. Gradually back off the accelerator and start braking to a stop, once you have the trailer under control. The harsh, abrupt unloading of the rear suspension, will make the issue worse.

Stu Cazzo

Unless of course you have a truck equipped with an anti sway feature...then you can also rely on that to overcompensate for the sway.
It will detect the sway and engage one or more wheels abs brakes to straighten out the unit.

While I agree most people don't know jack on trailer loading and cargo securement, there are other factors that will impact trailer sway.
Weather such as strong side gusts of wind and the road surface condition such as longer dips or side lane drops that are enough to cause the trailer to sway.