Easiest way is to edit the cPanel theme, although if you use the 'x' theme, or any other cPanel developed theme, the edit will get written over when cPanel gets updated. Solution make a copy of the theme and rename it to something else ( ie. xpanel or x2 or x3 ).
Additionally if you go this route and cPanel adds a feature/removes/completely reworks a portion of the cPanel your modified theme will be outdated, so a good idea would be to redo it all from time to time, after cPanel updates.
Also there is a `search` function, this type of question has been answered before.
Hope That Helps.