Kinda already on a roll, so I might as well keep going with it.....

    Have extra string with you at all times.
   
    Seems easy to remember right? Not really. When your constantly throwing down on the steets, or just practicing in your small bedroom, it becomes really easy to forget that every time your yoyo hits the string, it's adding pressure to it, and sooner or later it's going to snap from stress. Just saying.......