A properly balanced trailer is crucial to stable handling.
As a general rule of thumb, tongue weight should be 10-15% of the gross trailer weight. Maximum gross trailer weight should be marked on the trailer itself and should be strictly adhered to. Maximum tongue weight will vary from hitch to hitch and should be clearly marked near the ball mounting point. Cross weight is the load side-to-side or left vs. right on the axle. A 50/50 split is desirable. Improper tongue to trailer weight is one of the largest causes of trailer sway, so every effort should be used to secure your load to prevent the tongue weight from changing with the shifting load.
Towing adds weight and length to your vehicle, which translates into more time to not only accelerate but, more importantly, to slow down and stop. The additional load a fair distance behind the axle affects the vehicle more noticeably than the same amount of passenger and trunk cargo weight. Allow for additional space and time to switch lanes and slow down.
Swinging wider at slow speeds is common practice when towing but don’t forget to the same technique applies on surface roads and highways as well. Consider using a trailer brake system for loads that begin to max the vehicle rated towing weight. Many electronic systems are available for trailers with electric brakes and can be adjusted for each application.