Tricks of the Trade
AAA Tips
You want the string to be the same length, some players like them there standard length for A others like them a bit shorter.
As far as yoyos use the yoyos you like and are comfortable with, they don't have to be the same yoyo it just feels more consistant in your hand.
Binding both yoyos can be a little challenging; some players set their yoyos up to be responsive on their weaker hand and unresponsive on their stronger hand.
While you are learning it is important to be patient it takes time and you will get a lot more knots than usuall so have plenty of strings available.