Install the free cocoPPa app. Wait for it to load and open it.
Choose the icon you want
Press set up link
Press app search
Choose the app you want the icon to link to
Press the share button at the bottom of the page
Press add to home screen
Rename it if you want and then press done
It will be on your home screen
Move it to where you want it. The move the old icon to a different place. DON'T DELETE THE OLD ICON.
The creator of this guide has not included tools