If you're planning on doing it yourself, the only suggestion I can offer is DON'T! It normally takes 5-6 tries before a trained technician can do it without breaking something. You get only 1 chance.
So, if you're bring it to a repair shop or sending it to Samsung, they won't replace the digitizer (the part that registers your touch) on a cracked screen, they'll replace the screen.
If you try to replace the digitizer yourself (and it's tempting, it's cheaper than the whole screen), and you break something, Samsung won't touch it, most repair shops won't touch it, and you'll be left with a useless phone. And even if you do replace it without overheating the screen (you need a heat gun to replace it) or damaging something else, it may still not work because the screen itself may be causing the problem. So that's about $100 wasted.
Save money - have the screen replaced.