Creating a Grab Point
To some degree, the software that you are using affects how you create a grab point. Usually a null object is used as the grab point. Some people choose to use text objects because the text can give the animator information. For example, you could use "RF" and "LF" to indicate the right foot and left foot.
The object is then connected to the IK handle on the ankle. The easiest way to do this is to simply parent the grab point to the IK handle. This will allow you to translate, but problems might occur if you need to rotate the IK handle because the handle will rotate around the center of its parent. You can fix this by simply moving the parent's pivot point to match that of the IK handle. Another way to solve this problem is to create a similar effect with a point constraint. This will give you pretty much the same functionality as the previous solution, but without the hierarchy. After the grab point is created, the animator has an object that is easily accessible from any viewport.