I would recommend not to do speech therapy honestly.  It gave me tips that stayed with me for decades but not in a good way.  I'd elongate until I was blue in the face with forward flow and I finally decided to unlearn all of it and it helped tremendously.  The truth is there is no cure so some of the newer speech therapy courses focus on excepting and stuttering freely.  This is something you can encourage too and let them be by focusing on other things with them like school and sports and so on.  All this attention to their stutter just makes it harder.  It's like a thumb trap where the harder we try the tighter it gets.  If they are preoccupied with life it loosens and gets easier and easier.