If your home button is like mine and falling ,but not yet fallen out, it's quite annoying isn't it! But if you don't want to pull out your home button to replace it, you could just go on settings the on accessibility then click on assistive touch turn it on and a small button should pop up on your screen that you can move round. That's a home button! You can use it as a normal home button, but personly I find it a bit better than a normal home button... hope this helps!
P.S this is what I did and it helped!!