K.M.
I handle my sons impulses by making safe ways for him to act them out.
EX:
Need to jump. For my son this is an input need regarding his sensory and his hyperactive drive - he has an in home rebounder (kind of trampoline).
EX:
Need to open drawers. He has drawers that are HIS that he can open/close slam etc.
EX:
Needs to make noises or sounds that are flat out annoying. He can make them in his room all he wants, as loud as he wants.
EX:
Impulse to grab something. This one has been tricky - if he grabs it out of someone's hands he does not get to touch it for a period of time. Much like when you train a dog to sit and stay even though his treat/toy is right in front of him - that is my basic idea/inspiration.
My son is also 6 with adhd & SPD that has been diagnosed formally by a doctor. The only dietary aids that we implement is a reduced sugar diet. Basically, his diet is no more restricted than that of what I think a typical 6yr old should have. No soda, watered down juice, reduced sugar foods (but not food that has replaced the sugar with fake sugar). My son does not have cake and ice cream at a party - just one of the two. I find that the extra sugar puts him into overdrive and his crash is completely intolerable. I have not found any relief in the whole no wheat/dyes etc. diet suggestions.