Welcome Lakefr --
I too echo many of the points already stated.
After re-reading your post, I gleened three key points: (1) you are on Bear Island (2) you will be in both a boat and Jet Ski (3) most importantly- they're not yours! With that in mind, a "good" compass & chart is your best first move (quality GPS's can get pricey & are difficult to read and more importanly keep dry on a Jet). Both are best when "mounted" not loose in your hand i.e.. not your craft! I would also suggest that you get the "laminated" version of the chart ....... from experiance..... it's quite tricky trying to grab the paper version and re-fold it to the area you need (even if your stopped) on a jet ski. Finally, after spotting another of your posts on the forum -- you are in a relatively easy area to navigate a lenghty ride in eithor craft. Take the time to study the map, plan your route in your mind and go out and explore. I would suggest you initially venture in the Post Office direction as opposed to FL #3 i.e. less tricky/congestion direction. If you see a neighbor, don't be bashful -- tell him your situation and perhaps he would take you on a guided tour spin (pointing out the "real" hazards). I certainly would if asked. If I have learned anything boating at Winni -- it's that "local knowledge" trumps a chart, compass, depth finder, GPS, radar ..... well you get the point!
Keep in mind -- where you go safely with the Jet .... you may not necessarliy do so with the boat.
Enjoy!!