I too had a bit of difficulty at first. Two pieces of advice, well, three. First, your thumb is key. Matter of fact, while learning, 90 percent of your attention should go to thumb control. Really emphasize the amount of thumb pressure you apply to the spool during the initial part of the pitch. After only a few hours of practice, your thumb will get the hang of it.
Second, don't try to look just like the guy on the YouTube video. IMO, everyone will have a slightly different technique for pitching. You will learn yours. After all, you're basically just trying to pendulum lob your bait to somewhere accurately and quietly. It really is that simple.
Third, start with a shorter amount of line out. While holding your bait, it should be almost, but not quite even with your reel. I've also found that unless you are standing on something fairly tall, a longer rod makes pitching more difficult. Also, don't go for distance just yet. Go for thumb control. That's it. The distance will come later as you developed your technique.
Okay, that was more than 3 things, but I kept thinking of stuff. Hope it helped.