One of the problems faced in the world of scale model railroading is that model engines often do not have enough power to pull long trains up a grade, or sometimes even around a tight curve. In the real world, a train may be more than 100 cars, but in the scale model world, even a quarter of that load can cause the engine's drive wheels to start to slip. One solution is to apply rubber traction tires to improve the grip of the wheels on the track.
Remove one traction wheel from the packet, keeping the others in the packaging for later use, and place it on the hand towel so that it will not roll away.
Grip the tire with a pair of tweezers and heat the tire with a hair dryer to make it more pliable.
Pull the tire over one side of a drive wheel by maintaining your grip with the tweezers in one hand and guiding the tire into place with your free fingertips.
Push or slide the tire into the best position with a flat head screw driver, if necessary.
Repeat the process for all additional drive wheels on the engine.
Many modelers frown on traction tires since they are not realistic. Another option you might try is increasing the weight of the engine or adding more engines to pull the load.
Liquid rubber products are also available for use as traction tires.
Don't put traction tires on the contact wheels of the engine. The rubber will disrupt the flow of electricity and the engines will not work.
Don't overheat the tire. At close range, a hairdryer can melt or deform rubber. Hot water is another option, though much more messy.