I can whip the string into the yo-yo , but when I do it , the string is either backwards , or knotted up in the yo-yo.
Any help or advice? I would appreciate it! 
Here’s for a tip: You know when they tell you to put the string around your thumb and whip it?refter you hook it around your thumb, turn your hand (Wrist) towards the right. Not arm, turn your hand right. When you whip it now, aim the string on the left side, into the yoyo.
How this helps you is that when you don’t turn your hand. Both strings of the slack will stick together. If they do, it’s very hard to make the particular left string hit the yoyo. Turning your hand seperates them.