In order to prevent the right foot of the character from sliding awkwardly, I selected the right foot controller, and in the character tools menu right clicked over said controller and selected 'create aux effector'.
This created an effector correlating directly with the translational and rotational data of the controller at the exact key frame that the effector was made. From here I keyed the weight of the aux effector on the controller to 100 where the foot needed to remain steady, and zero where the effector was to have no influence on the controller at all; an effector can be made to influence a controller translationally, rotationally, or both as needed. In this particular animation, I wanted the foot to remain in one stationary position, and therefore had this effector influence the controller in all ways possible.
*Note: As depicted below, the influence of an effector can be seen as an outlining yellow box that is visible when the effector has any influence on the controller and is gone when the weight of the effector is at a value of zero.
Being that the effector is set to one position of the controller, if it should not have a strong enough pull to completely eliminate any sliding or shaky data, there is also the option to key the controller while it is still being influenced. This will snap the controller to the exact position that the effector defines (as depicted below). If necessary, several frames can be keyed to completely restrict movement and eliminate any unwanted motion of the controller.
In addition to simply pinning a controller down, an effector can also be used for several other types of applications, such as maintaining a rotational pull on the head or neck of a character as they walk, on a hand holding an object (for instance keeping the aim of a gun the same as a character moves forward or backward), etc.