This tutorial assumes that you've already created your slider. To set your revolution slider to be responsive you will need to:

1. Log into WordPress.
2. Click on the tab 'Revolution Slider' on the left side of the WordPress admin.
3. Under the 'Revolution Sliders' section, click the slider you want to edit.
4. Select the option 'Custom' and set the responsive sizes in the fields below.
   
5. Click the 'Save Settings' button.

Refresh the page and minimize the browser window to test the responsiveness of the slider.