1. For activating actions palette press F9 key (Option+F9 on Mac), there is also alternative command "Window > Actions".
2. To load actions into Photoshop, click on the tiny button on the right hand side of the actions palette and select "Load actions". Standard dialogue box opens and you can locate actions on your computer.
   
3. Loaded actions will appear in the actions palette, select the actions you wish to run and click on the play button. Once you have loaded the actions, they stays ready in the pallete.