I want my icons to change color on hover

If you are using font awesome then you can target icons with the class fa. Icons behave like text would, so we can adjust the font-size, color etc. To change the color on hover you would write:

 .fa:hover{
     color:blue;
 }

To add a transition so that they change color smoothly you could add:

 .fa{
    transition:all 1sec;
 }

 .fa:hover{
    color:blue;
 }