To set the thickness of your keyframes in the Time Slider
Key thickness is measured in pixels. The minimum key thickness is 1 pixel and the maximum is 63 pixels.
To set the color of a curve’s keyframes in the Time Slider
The spreadsheet for the selected animation curve appears in the Attribute Editor.
All the curve’s keyframes in the Time Slider are now the Curve Color you selected.
To set the color of individual keyframes in the Time Slider
and then press on the number pad.
The keyframes you selected and set the -tds flag for are now drawn with Time Slider Tick Special color in the Time Slider.
For more information on this flag, see keyframe in the MEL Command Reference documentation.