to make the most out of him being a child, don't use the term so much. growing up i just refered to it as my handwritting thing and did not blame it on so many things. some thing would have helped- i have trouble with spatial stuff and it would maybe have helped to know that but let him find his own troubles and strengths. if something really gets to be a problem then tell him it's not his fault and he is not stupid. do definetly get the modifcations that he needs- typing things or extra time, but only if it will help. you can try asking him, when he gets a few years older maybe, if he wants stuff like extra time, if it will help him. if it doesn't help him, then don't alienate him from his classmates. good luck and i'm here if you have any questions
Given the age we live in, he probably already has a computer. If he doesn't, he's going to need a laptop for school. Also if possible his notes should be given to him on paper. Some people like to think this is something you can overcome by forcing yourself to write by hand, but in my experience it's best to avoid it whenever possible. Hopefully his teachers can get over their tendency to demand to see rough work with improvements, he should be doing all of his writing with a keyboard. Speech recognition software is a good idea too.
Dysgraphia doesn't have to be a problem as long as no one makes a problem out of it. I say all this as a dysgraphic adult who had a lot of trouble in school because of undiagnosed dysgraphia, not as an kind of medical or psychological expert.
Remember that anxiety is one of the symptoms. If and whenever he feels the strain from writing to the point of anxiety it's important not to push him to try harder, but rather to get him to relax and approach the work fresh later.