Higher temperature increases collisions
When the temperature is increased the particles all move quicker. If they are moving quicker, thery are going to collide more often
Higher concentration increaes collisions
If a solution is made more concentrated it means there are more particles of reactant knocking about between the water molecules which makes collisions between the important particles more likely. In a gas, increasing the pressure means the particles are more squashed up together so there will be more frequent collisions.
Largere surface area increases collisions
If one of the reactants is a solid then breaking it up into smaller pieces will increase the total suface area. This means the particlkes around it in the solution will have more area to work on, so there'll be more frequent collisions.