Use Auto Key

NoteAutomatic keyframing may generate extra keys for ikHandles if their ikBlend attribute is turned off.

For example, if ikBlend is off, but snapEnable is on for an ikHandle, the handle moves to the position of the end-effector. This lets you create an arm skeleton with an IK handle, turn ikBlend off, rotate the shoulder joint, and have the ikHandle snap to the wrist position. If auto keyframe is on, and you already have an animCurve for the ikHandle translation, the auto keyframer generates more keyframes because the handle has moved.

To avoid this problem, turn off snapEnable or auto keyframing.

To Auto Key an animation

Turn on Auto Key on the Range Slider.
Set a key on any attribute of an object.
Go to a new time in the Time Slider.
Change the value of the previously keyed attribute.
A key is created for the attribute. You can create another key by going to a new time and changing the value of the attribute again. For more information, see Auto Key.

To hold Current Keys with Auto Key

Turn on Auto Key.
Select the attributes you wish to use Hold Current Keys on; set a key at the starting position.
Create a walk cycle where a foot touches the ground at time 30.
Later in the walk cycle, for example, at time 60, another key is needed for this position.
Instead of figuring out exactly which attributes are being keyed, move to 60 and select Animate > Hold Current Keys.