Place your finger onto the icon until it starts to "wiggle". Drag the icon to the dock (if there's not enough room, take another icon off the dock first). Press the home button to stop the icons from wiggling. Done.
Place your finger onto the icon until it starts to "wiggle". Drag the icon to the dock (if there's not enough room, take another icon off the dock first). Press the home button to stop the icons from wiggling. Done.