How can I increase the rate of reaction between two substances, without changing the chemicals I use?

Rate of reaction is based on collision frequency: chemicals react when molecules come into contact with each other with enough energy to react. If you want to increase the rate of reaction, you need to find a way to make the molecules collide more, for example:1) Increasing temperature- when molecules are heated up, they gain energy and vibrate more. These increased vibrations mean that molecules come into contact more often (collision frequency increases) and come into contact with greater energy, so more of the collisions result in a chemical reaction taking place.2)Increasing pressure (of gas)- increasing the pressure of a gas means there are more gas molecules in a set space, meaning they can collide more, so rate of reaction increases.3)Increasing concentration (of liquid)- increasing the concentration of a liquid means there are more molecules in a set volume of liquid, meaning they can collide more often, so rate of reaction increases.4)Increasing surface area (of solid)- powdering a solid increases the surface area available for a reaction, and means that more molecules of the chemical are exposed, as they are at the edge of the solid, not trapped in the middle, and can collide with molecules of a different substance and react.