Set up an account on Sail Clear. Enter in the boat information. Documentation should be on the boat, but ask the base if not, or if you have any specific questions on form. Also go ahead an enter all of the crew. Then create a departure notice on Sail Clear a day in advance and submit that. You will need to get a $25 annual subscription to Sail Clear. Then check out of customs at Jost or West End. Bring passports, cash, and boat documentation (be sure to have the CRVL).

Also go ahead and create an account on CBP Roam app for checking in. You can scan all of your passports for easy entry, but still need to set up the boat. When you get to your USVI anchorage, submit the arrival via ROAM. It may take an hour or two to get checked in (or could be faster). They will notify you when it is done. If there are any issues, go to the Customs office in Cruz Bay or call them. If you go to Maho first and need cell coverage for the Roam App, stay out closer to Francis as the cell coverage is bad closer to shore.

I echo what Zanshin said and would stay (circle) around St. John. Specifically, I would recomend:
Spend a day at Maho/Francis - Maho Crossroads, hike to Annenberg Ruins
Head to Waterlemon Cay for a snorkel
Check out Trunk and Cinnamon - if conditions are settled you can use their balls for day stops
There is a great hike from Hawksnest to The Windmill Bar, if you have a fit group - straight up and steep.
Spend a day/evening at Caneel Bay/Honeymoon. Lunch at Honeymoon. Dinner at Zozo's in Caneel, or head in to Cruz bay for dinner - cool town an tons of options.
Then head down to the southside and stay at Lamshur or Salt Pond (only 3 balls I think now) for a quiet night. Ram head is an amazing hike and definitely worth it and
Tons of snorkeling options around Lamshur and Salt Pond. Also consider, hiking the Reef Bail trail to the waterfall (petroglyphs) and ruins. Long hike.
Or maybe head down to Coral Bay for lunch at Lime Out (floating taco bar) - expensive but really good. We have anchored there for lunch and come back to Lamshur for the evening.

And don't forget to send your arrival notice in Sail Clear a day before heading back in. Check in at West End or Jost.