Hi,
A few points I would like to make:
First - thanks for posting this, looking for advice, and admitting you are inexperienced. That's the best way to gain knowledge and eventually experience.
I believe that your your current 86SC can do auto guidance, but you may need to update the charts in it. According to Garmin, the US LakeVu G3 charts contains auto guidance:
From the garmin site:
Experience unparalleled coverage and brilliant detail when you’re on the water. LakeVü g3 inland charts provide exceptional coverage, clarity and detail with integrated Garmin and Navionics content on more than 18,000 lakes — including more than 160 Garmin Elite surveyed lakes.
Auto Guidance Technology
The Auto Guidance feature1 uses your desired depth and overhead clearance to calculate a route and suggest a path to follow.
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The GPSMAP86SC is listed as a supported device, but the user manual is not clear on if auto guidance is supported.
Now for some more 'stuff' from me. This will probably get long, so read on or stop, up to you.
IMO the best way to plan a route is to look at a number of charts, starting with a small scale / big picture so you can see the entire route in one chart, and then moving to bigger scale / smaller picture so you can see any hazards you need to be aware of or avoid.
Back in the day, I used to pencil in a line on the chart, write down the course heading, record my position on the chart hourly, etc. I haven't done that in years.
There are many many ways of actually using the route information you have generated. As written by posters above, some people make a note of hazards and then just sail along, keeping a general idea of where they want to go and things to avoid. Others add a waypoint or two and use that.
For me, personally:. If I am going to a specific destination, even if it's a short trip, say 10nm, or a destination I have been to many times, I ALWAYS create a route (or use an existing one), load it onto my plotter and run the route while underway. It is super easy to do (more on that later), provides a number of benefits (to me), and allows me to focus MORE on what is going outside of the boat and LESS on mundane tasks like where am I, what is coming up next, what do I need to avoid, etc.
I am admitted gadget fan and I love the technology, so maybe it's just me, but I can't of a reason to NOT use all the tools I have. A good friend of mine, a very experienced sailor, boat owner, and talented racer, doesn't care for electronics and almost never uses his. To each his own.
I remember my first 'long distance' sail. After 1 year of sailing experience I had bought a new to me boat and I needed to deliver the boat from the brokerage to my home port. The distance was 35nm and started in a new port. I was super nervous about the trip. I studied the charts, charted the trip in the chartbook, and created a simple route in my old Garmin handheld. The trip turned to be just about perfect - great sailing weather, I timed the currents correctly, the boat worked perfectly, etc.
MY TECHNIQUES:
I run the Navionics boating all on my computer, phone, ipad, and tablet. I use Navionics charts on my B&G Zeus 3S plotter.
I will start with the boating app, usually on my ipad, and pick my starting location and destination, and let Navionics pick a route. Navionics route creation is pretty good. It will go NEAR Aids TO Navigation (ATON) but not select them as waypoints.
Depending on how long the trip will be, if I have been there before, if I need to go under any bridges, or anything new or different, I will consult my paper charts.
Then I will look at the Navionics and I may manually edit the route. I have noticed that Navionics is way more conservative than I am. On a 50nm trip I can usually shave off 5 or so miles and save valuable time.
Now I have a route I am happy with.
Before I start my trip I transfer the route from my phone to my Zeus plotter. This happens automatically once I connect the phone to the plotter via wifi.
Before I depart I usually 'RUN' the route and off I go.
When sailing (or motoring) to my destination, I like that the plotter automatically calculates and displays my speed, VMG to waypoint, time to next waypoint, distance to next waypoint, bearing to waypoint, heading, cross track error, time to destination, distance to destination, and a bunch of other useful information.
I don't NEED that information, but I like having it, and it's free. As the trip progresses I can easily determine that yes, I am where I think I am by visually seeing ATONs, etc. I quickly know that in about 15 minutes I will be passing this or that hazard and I should pay more attention to boat traffic etc.
MOST of the time my autopilot will be on and IT will run the route. When I arrive at a waypoint the autopilot will automatically change to the next waypoint. I DON'T LIKE THIS and wish it would beep and require me to press a button or something, but that's the way it works. So I am sure to be alert and prepared BEFORE a course change.
Last year I did a few long distance trips.
One was a return from Bermuda to NY on a friend's boat. I was not the navigator, only a crew, but I still created two routes in my handheld garmin and in navionics on my phone. The routes were simple - depart Bermuda and to go New York City, OR depart Bermuda and head to Greenport. Simple as could be.
The other trip was a two week trip to Portland Maine. The trip there was done non stop, through the Cape Cod Canal. So the entire 250 nm route was entered. The return trip was done one day at a time. So each night I would plan the next day's destination, including my routing. This was all uncharted waters for me, so I spent a good amount of time on the route. It all worked out well.
Anyway, good luck to you.
Barry