My 19 year old son finished Navy Boot Camp in December and is now in A School at Great Lakes to become a Fire Controlman.
My background was Army, but many truths of surviving basic training are universal. I had told him:
Mouth shut--eyes/ears open
Strive to only get punished when it is group punishment
At the lower enlisted level, the military is one of the few remaining pure meritocracies--strive for excellence
Work together--help your buddies that are struggling
Take things one day at a time--you can stand on your head in the corner for 8 weeks (i.e. this will all be over in a blink)
As far as support goes, the Navy is pretty strict about what can/can't be mailed to the recruits. Letters and documents are fine. The Navy takes away everything that has allowed easy communication and leaves them with the US Postal Service. No email, no computers, no cell phones, very few phone calls (I think we talked to him 3 or 4 times during the 8 weeks--the first call after arrival is about 90 seconds, lol). I tried to write my boy at least once a week and encouraged other family and friends to do the same. I received 2 or 3 letters from him in return--and I will probably keep those someplace safe forever. We just don't write on paper by hand much these days--and letters are great!
Keep your communications and letters newsy and light. Tell your recruit stories about what is going on with you that day. Ask questions about his new work/life--but don't ask about things like "are you lonely, homesick, etc.?" For instance, I asked about what the Navy food is like; what his Chiefs/LPOs were like; how he liked the uniforms, etc. Print a page of photos from the computer/printer and include it...but again, keep the photos fun--siblings making funny faces, family pets being crazy, etc. The recruits won't be getting any news there...Include some light news clippings of feature stories he'd be interested in--they will pass that stuff around the barracks/compartment.
Anyway, just some ideas. Best of luck to your future Sailor! I'm proud to be a Navy Dad!