What methods of increasing frictional force do you know?

The formula for the friction force: Ftr = M * N, where M is the coefficient of friction, which depends on the properties of the rubbing surfaces, N is the reaction force of the support.

N in the simplest version, when moving on a flat surface, is equal to mg, where m is the mass of the body, g is the acceleration of gravity.

For the Earth, g = const, i.e. this is a constant value.

Means Ftr = M * N = M * m * g, therefore it depends on the coefficient of friction and body weight, and the dependence is straight.

Thus, in order to increase the friction force, it is necessary either to increase the mass of the moving body, for example, by loading it, or to increase the surface roughness.

To increase the roughness, for example, sand is sprinkled on the icy streets, studded tires are installed on cars or chains are wound on wheels.